Story highlights Simma Lieberman was not a proponent of same-sex marriage until her partner of 18 years died

She had few rights with regard to her partner; had she been married, she would have

Neither Lieberman nor their son, Avi, could collect federal benefits available to married couples

Lieberman: My views on same sex marriage have changed; civil unions are not enough

I wasn't always a big same-sex marriage proponent. But the past 10 years changed that.

In 1984, I met my partner Sandra Brown when she sold me a ticket for a benefit concert for a mutual friend with breast cancer. On April 7, 1985, after attending her first Passover dinner at my house, she told me she loved me and wanted to spend the rest of her life with me.

Sandra was African-American, born in Berkeley and raised Catholic. I'm Jewish, Caucasian, and raised in the Bronx.

I had more in common with her than anyone I had ever met.

We were together for 18 years. In 1994, I gave birth to our son Avi. He had two moms who loved him.

Avi's other mother worked from 6 a.m. until 3 p.m., picked him up from school every afternoon, helped him with homework and taught him things like how to analyze movies. I was traveling a lot, meeting with clients, speaking at conferences, and often working on weekends.

Simma Lieberman

When I was home, I took him to school in the morning and attended school functions. While Sandra helped him with his science projects; I cooked dinner and went grocery shopping. While I was writing proposals, Sandra was teaching him to ride a bike.

All of that changed on January 26, 2003, when Sandra suddenly died from a massive heart attack.

Over the 18 years we were together, we didn't pay a lot of attention to the discussion about same-sex marriage. There were other issues that were more important to us, like where Avi was going to attend preschool, how to get him to sleep on time and celebrating Hanukkah at our house and Christmas and Kwanzaa with her family.

When companies offered to recognize domestic partnerships, we thought it was great that now people in same-sex relationships could get health insurance benefits, visit each other in the hospital and inherit property.

We thought that was enough. We had no idea what marriage really meant. To us, it was just a ritual for other people, but meant no real change. It was a "nice thing to do," but wasn't available to us.

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But on January 26 that year, I discovered that despite our 18 years together, we were just considered friends, and neither our son nor I had any legal rights with respect to my union with Sandra.

If we had had the option of marriage, we would have gotten married, had a wedding and invited friends and family. We would have taken it for granted that we would get married, like everyone else. We didn't fully understand domestic partnerships or the bureaucracy couples had to go through to get recognized. We didn't see the advantage of having to prove that we'd lived together for any length of time.

Heterosexual people who have spent one night together or who never met in person but online can get married. You see, legal marriage confers all the basic rights without any question, without having to do extra paperwork to be recognized.

And I would soon learn that civil unions or domestic partnerships were not the same as legal marriage at the federal level. Those of us in same-sex relationships should have the same benefits as heterosexuals and not be satisfied with same-sex second-class citizenship.

Sandra was at a friend's house when she died. Avi and I were notified about her death when we came home to find a note on our door telling us to call the coroner's office. I told the people there that I was Sandra's partner, but they said that legally I could only be considered her friend, and that only her blood relatives could make any decisions about her person and her belongings.

Her brother and I knew she wanted to be cremated, and he made the arrangements. We decided together on a date for her memorial. I also wanted to spend some private time with our son and some close friends in the sitting room at the crematorium before cremation.

When I called to make arrangements, the funeral director told me he was sorry but I had to get permission from her birth family for Avi and me and the specific people I wanted to bring. At first it was difficult to get permission, since her brother and his family had their own grief to deal with and making the arrangements was not that simple.

We were fortunate that, unlike other people we've known, her family was supportive of our relationship and we were allowed to be with her. But they weren't lawmakers.

Had they not been supportive, we could have been denied the time we had to sit with her before cremation. Had Sandra and I been married, I could have just made the decision and informed the people at the crematorium.

We weren't the people that were consulted by the coroner, the crematorium, or anyone else in any authority because in the eyes of the law, our relationship had no legitimacy. Our 18 years -- 18 years -- together carried no weight. Avi and I had to sit on the sidelines and wait for permission. We were further traumatized and felt invisible.

We were fortunate that Avi's elementary school teachers showed great compassion. His third-grade teacher had a class memorial, and I was able to spend as much time as I wanted helping out in her classroom.

For Avi, the world as he knew it ended. He worried all the time that something would happen to me, and he stopped believing in childhood fairy tales, happy endings and the mysticism of the world. There were no longer portals in the tree trunks in the woods that led to other worlds.

In an instant, I became a single mother, with a single income. My partner had worked for years. Had we been allowed to marry, our son would have gotten her Social Security benefits.

No matter how many states, communities, cities or counties allowed civil unions, our son still would not be able to receive her Social Security benefits.

I have changed my mind about the importance of gay marriage. I no longer think that civil unions are enough, and I no longer think it's OK to not have the same rights as everyone else.

And I know as the surviving partner of Sandra Brown and mother of our son Avi that laws alone don't equal inclusion. People don't automatically adjust to change or know what to say even if they're supportive.

I've become an outspoken supporter of gay marriage. It took my own personal tragedy to reach that point. I am heartened and inspired to see a groundswell of support. I look forward to the day in the near future when no one else will have to go through the same experience as I did with our son

And no, civil unions are not enough.