Libby Phelps Alvarez was raised as a member of the Westboro Baptist Church, a vitriolic group founded by her grandfather, Fred Phelps. Famed for picketing funerals of soldiers with anti-gay signs, the Topeka, Kan.,-based organization, with its estimated 70 members, has become infamous for its extremist hate speech.

Four years ago, Alvarez, now 30, left the church — and she is now supporting Planting Peace, a nonprofit that recently bought a house across from her old church and painted it with gay-pride-themed rainbow stripes and titled it the Equality House. Alvarez plans to work with the group’s founder, Aaron Jackson, on a new anti-bullying initiative — as far as one can come from a childhood of waving signs reading, “God hates f - gs.” A physical therapist, she lives with her husband, Logan, in Lawrence, Kan., close to her hometown. She tells The Post’s Sara Stewart her story.

I’m sitting in the living room of the Topeka rainbow house, looking out across the street at the church that used to be my home. I’m so close. And I’m really nervous. I don’t want anyone to see me. I don’t want to disappoint my parents.

But I like hanging out with the guys here. I’ve been here a few times now. I like how open they are, and how I can have conversations with them about anything. Growing up, I would always be afraid of getting things wrong, afraid of what my family would think of me if I did.

PHOTOS: ‘I LEFT MY FAMILY’S GAY BASHING CULT’

I knew what the rainbow colors meant when I first saw the house — I’ve picketed gay pride parades before, after all. I don’t quite know what I think about it all. It’s not like I want everyone to be gay. But I think everyone should be treated equally.

This is not the kind of teaching I grew up with. My grandfather, Fred Phelps, is the founder of Westboro Baptist Church.

Gramps, as I called him, is a Southern gentleman. You just want to be in his orbit. He’s always very sweet with Gran, always gives her kisses. But with Gramps and my dad — Fred Phelps Jr. — the only way to get their love and affection was to talk about hell. I remember sitting by the pool in the backyard when I was young, writing in my pink notebook about hell and the descriptions of it. Gramps came up to me and kissed me on the forehead and said, “I love you. I love you. I love you.” Three times in a row.

He would make me poached eggs for breakfast, and then we’d sit around and he would talk about the sermon for the upcoming week. It was always about how “f - gs are dooming the nation.”

There are about 70 people in the church, mostly family. We had about 10 houses in the neighborhood, and a communal backyard. Gramps and Gran live in the house that’s also the church.

In the old days, Gramps was a Democrat and a civil rights lawyer. He ran for governor in the ’80s. I remember driving around in his red truck in parades, throwing candy and stuff. We would have these big barbecues in the backyard. Al Gore came to my house for a fund-raiser once.

When I was 8, Gramps went to nearby Gage Park with two of my cousins, who were about a year younger than me. This park was known for homosexual gatherings. When he came back, he said these men started propositioning the boys — though you know, I’ve never actually asked my cousins whether that happened.

Gramps went to the city council meeting and wrote letters. And the next thing you know, we all started picketing, every single weekend. Eventually it became every day, no matter what. Afternoon pickets and evening pickets. Because you’re doing God’s work, telling everyone they’re going to hell.

The whole family talks about homosexuality, every single day. And it’s always about how homosexuals are dooming the world. They talk about fornication and divorce, remarriage and adultery, but the main thing is the homosexual lifestyle. It wasn’t a personal hatred toward anybody. We were taught that we were doing a loving thing.

Either you are one or you’re enabling one, and so everybody — except the Westboro people — is going to hell.

Church was on Sundays, for an hour. All the women had to wear head-coverings, because women are seen as submissive.

Gramps would always do the sermon. He was so good at it, so intense. He would talk about topical things that were going on, and it would always come back to homosexuality, nearly every single time.

We weren’t allowed to celebrate any holidays at all, because they’re all too pagan, even Easter and Christmas. We could only celebrate birthdays, so those have always been a big deal for me.

We went to public school, but we weren’t allowed to go to dances or anything like that. We were mostly friends with each other. You weren’t supposed to date, obviously. Gramps would preach about that: “If I hear of any of my grandkids going around having sex with anyone . . .”

The picketing was a social thing for us — it was a way we would see our cousins. We would just call each other, like, “You going to the 5 o’clock picket? Me too. I’ll see you there.” We would use it to go on vacations. You go, you picket, you do some fun stuff. I have a picture of me in Hawaii with two signs: “God hates f - gs” and “God hates Hawaii.” Why does he hate Hawaii? Because we wanted to go there!

When 9/11 happened, I heard it on the radio in the car. I was actually driving over to the church. It was jaw-dropping. I thought, “Oh my God. I can’t believe that happened.” And then I get to the house and everyone was celebrating, like, “This is awesome! God is punishing this nation!” So I had to change, and be like, “Oh, OK, that’s awesome.” So I did. That’s what I thought.

Around 2007, my cousin Megan and I would go to a rec center at a nearby university to play volleyball. And this guy Blake came up to us and asked if he could hit with us. He seemed really personable and outgoing, really nice. He didn’t say anything about being gay. But I’ve been around homosexuals my whole life, just from picketing them. His mannerisms made me think he might be. Afterward, I looked at Megan and said, “Do you think he’s a f - g?” We didn’t know.

Blake told me later that his friends, and the people at the rec center, were saying, “Do you know who you’re playing with? You’re playing with those Phelpses!” But he kept hanging out with us.

One time he was driving down 17th Street in Topeka, and he saw me and Megan picketing with some people. And he honked and waved at me, and I said, “Hey!” and smiled back. It was confusing.

In 2008, I graduated from University of Kansas Medical Center with a doctorate of physical therapy. I had been living at home the whole time I was in school.

One of my first patients was this guy named Logan. When he came in, I thought, “Whoa, he’s cute.” I didn’t say anything, because I’m very professional! But also it wasn’t like it was a possibility. If anybody in the church even thought you were lusting after somebody, that was a sin. But I didn’t lust. I just thought he was cute, and I kept it to myself.

Then in 2009, my mom and dad, my sister Sara and me took a trip to Puerto Rico. We weren’t allowed to picket there, but we went anyway — we took a whole bunch of photos, including one of me and Sara in our bikinis at the beach.

When we got back, Gramps said to me, “I haven’t had a picture of you guys in a while. Can I get one?” I thought that was the best one, so I gave it to him. And he liked it. He was like, “You guys look like models!” He always said that kind of stuff.

So I didn’t think anything of it until my cousin Megan called me on the phone and said, “Why were you wearing a bikini? I don’t think it’s appropriate.” And I stuck up for myself. I said, “You’ve worn a bikini before. We used to be able to wear them. And now it’s against the rules? It wasn’t like I was trying to pick up a guy or anything.”

Then my Aunt Shirley called and said, “Can you come down here? A few of us want to talk to you.” I showed up, and 30 church members had filled up the big game room. Like a show was being put on or something. And they started in: The initial issue was the bikini, but the bigger problem was the way I was reacting. Because I had stood up for myself.

I wanted to throw up. It was the most intense thing. Because I’m thinking, I better shape up or I’m going to go to hell. Then I heard Marge, who’s my other aunt, in the other room saying, “She’s too far gone. There’s no hope for her.”

That was on Wednesday, March 11. On Friday the 13th I left for good. It was a really hard decision for me to leave. But things were just getting more and more extreme in the church — like praying for people to die.

Nobody knew I was leaving. My mom and dad were on an out of town picketing trip. And my sister was out of town, too. I didn’t tell anybody else in the family.

It was in the middle of the day. My boss and two other people from work came to my family’s house and helped me pack up my stuff and I went to my boss’ place, where I lived for a few months.

Blake was one of the first people I saw after I left. Not because of him being gay or anything. He was just always really nice to me. And I remember talking to him and him saying, “So what do you think about gay people now?”

And I said, “I still think it’s wrong!” Because when I first left, I did think that.

That was the first time he’d asked me anything like that. And he said, “Oh,” and kind of looked down. I’m pretty sure he thought I would tell him he was going to hell if he was.

Soon after I’d left, Shirley sent an e-mail saying, “Your mom and dad and sister want no further communication with you.” I learned later that my mom had called the clinic where I work on Friday, not knowing I’d moved out. That was the only time she’s ever tried to contact me.

One of the first things I did after leaving was get a haircut. Women can’t cut their hair in the church, because of First Corinthians 11:14: “If a woman has long hair, it is a glory to her, for her hair is given her for a covering.” You shouldn’t cut it off because you’re cutting your glory off.

The whole time I was nervous. I was like, “Oh my God. I can’t believe I’m doing this.”

When I first left, I thought that I was going to die driving on the highway. When I first got on an airplane, I thought it was going to crash and I was going to die, because God hated me now. I still get scared.

A few months after leaving, I was shopping downtown and recognized Logan, my cute former patient. I was like, “Hey, I know who you are.”

We started dating and early on I asked him, “Do you know who Fred Phelps is?” And he said maybe he’d heard the name, but he didn’t really know. And I said, “Well, I’m his granddaughter.” I told him to go home and research it.

The next time I saw him, he told me he had. And then there was a long pause. I was like, “Just say it. Whatever you’re going to say, just say it.” He said, “It doesn’t matter to me.” That my past didn’t matter. And he liked me for who I was. Because I didn’t do it anymore, he didn’t care.

We dated for about two years and then we got married in Cozumel, Mexico, on July 9, 2011. Three of my cousins who’d left the church came to the wedding. I was sad, because I wanted my parents there. My mom and grandma had given me these rings when I was younger, and I wore those. The one from my grandma had four birthstones on it.

I walked down the aisle by myself. I didn’t want anybody to walk me. I felt lonely — everybody wants their dad to walk them down the aisle — and I could have asked a cousin, but I figured, I’ll be a strong independent woman and do this by myself.

We’re happily married but my past still haunts me.

A few months ago, I was having a really stressful night. I had a little breakdown. I went to Blake’s house, and we went driving around. I was just telling him everything, spilling my guts.

And then in the middle of all this I said, “Blake, would you just tell me that you’re gay?” That’s just my personality. I’m nosy. I could tell he was hesitant to say. He was living with a guy at the time.

He finally did. And I just started laughing. He said, “I knew you’d be fine with it and you’d still be my friend. But what I was afraid of is that you might tell me I’m going to hell. And I don’t want to be told that.”

But I didn’t tell him that.

The day before Easter I took my little cousin to Topeka because I thought she would like to see this colorful house I’d heard about, right across the street from the church. I drove over the long way, so I wouldn’t have to pass all my families’ houses. I was really nervous. I was shaking. I didn’t want to get out. The first time I got that close, I was like, “I can’t believe I’m doing this.” But I walked up and I sat there on the porch for a little bit.

A tall man with dark hair came out of the house and introduced himself as Aaron Jackson, the founder of Planting Peace. Immediately I was intrigued and we made a plan to have dinner. Over the meal with Aaron and his associates, Davis Hammet and Rob Gisser, they told me about their plan to start an anti-bullying program. Aaron asked if I’d be a part of it. I don’t know if I want to give a speech or anything! But I don’t believe in people bullying people for any reason. So we’re talking about it.

When I was in the rainbow house last week, I saw my parents go by on their daily walk. I hadn’t seen them in four years. And I couldn’t go to them, couldn’t talk to them. It wouldn’t be productive. I just watched them walk by and I started crying.

My dad will see this story, because he’s the one who weeds through press. And if he thinks it’s worth forwarding on, he’ll forward it to everybody. And then someone will be like, “She’s following her lusts, she’s going to hell.”

But I want to tell my parents that I love them. And I want to say that my parents were good parents.

I don’t know if they would ever leave the church. But my cousin Megan left a few months ago and she’s one of the last people that I would have thought. And now her sister Grace and my sister Sara have left, too.

So it’s a possibility. My parents could leave. I would want them to. Then I can see them again.

In the meantime, I hope I can help some of my young relatives when they get older. That’s my main goal, why I want to stick around in Kansas.

I want my cousins and my nieces and nephews to see that the world isn’t mean and hateful and evil and full of vicious people. We were told there’s going to be heartache and sorrow and disease and sadness in the world outside the church. And there is sadness at some points. But overall, it’s a fun adventure.

I don’t really think my personality has changed much, but I think my ideas on life have changed. When I had first left, if I would see a homosexual couple, I would scrunch up my nose. Then it got to where I still thought it was wrong, but I wouldn’t say or do anything. And now it’s to the point where it doesn’t matter to me. I don’t really care if somebody is gay. I know that I want to be good to people. I still believe in God. I just think that he’s more forgiving.

Ultimately I don’t think I have the right to say who is going to heaven or hell. I think I’ve always felt this way, but until now I didn’t have the courage to say it.

sstewart@nypost.com