TL;DR: I caught my wife cheating on me over a year ago. I stayed with her for the sake of our children, but I haven't been able to get it off of my mind since.

It has been 476 days since I confronted her about it, how do I know? Because every time I catch myself thinking about it I tell myself, "It's only been X days, maybe you won't think about it tomorrow".

So to go back to the beginning I had just taken on a new project and new responsibilities at work. I was working a lot of hours (60+ per week) and was noticeably stressed. It was in May of 2015 that I noticed that she had added a password to her phone. When confronted about it she told me it was because she was planning my Father's Day present and didn't want me to ruin the surprise. About a week later she came to me and told me that she felt guilty keeping a big secret from me and told me that she was having our neighbor, a contractor, build a home office for me as my present. It struck me as odd as in our 6 years together she has never said she felt guilty about anything and always insists that she never regrets anything in her life.

Time goes on, her phone is still password protected, and things don't feel right. I see her using her phone and smiling to herself more and more often. But when I ask her what she is doing she says nothing and puts her phone away. So one morning I wait for her to get in the shower and I grab her phone before it requires the password. I go through her messages and find that she is texting the neighbor, "I am all covered in frosting, you wanna lick it off?". There were no other messages to the neighbor but I found out later that was because she had setup her phone to delete messages after a certain amount of time. I felt uncomfortable with it but I knew she had a perverted sense of humor and I thought she would never do anything to hurt me.

More time goes by and the neighbor is spending more and more time at our house but the office is being completed slower and slower. I can't help but worry that something isn't right so I start checking her location using Google Timeline. It was at this point that I realize that there are large gaps in her GPS history because she was turning off her phone's GPS. Fast forward to July and at this point the paranoia is driving me nuts so I tell her that I need to install new anti-virus on her phone. While she has it unlocked for me I install Anti-theft software so I can remotely turn the GPS back on and set up At&t Message Backup and Restore so I can read all of her text messages from that point on my computer.

The next day my mother asks to spend time with my two kids so my wife drops them off with her and has the day to herself. I watch my wife's activity from work as she spends the day trying to meet up with the neighbor but is unsuccessful because he is busy with another job site. That night we get the kids back from my mom's house and we go out to dinner with the neighbor, his girlfriend, and his son. My wife and his girlfriend are having a good time drinking, laughing, and just joking around. His girlfriend mentions that should would like to see Magic Mike XXL, I say it's a good idea I'll watch the kids so my wife and her can go. So my wife and her go and the neighbor and I go back to my house so the kids can play video games together.

The kids are back in my son's room playing games and the neighbor is sitting across from me on the other couch. It is at this point that my wife starts texting him. She is describing sex acts she would like to perform with him and he is reciprocating. She tells him to check his snapchat and at the same time I get a snapchat from her too and it is her fingering herself in a bathroom stall. They keep talking, trying to figure out when they can meet up and have sex. They decide on Monday morning after I go to work. So in my head I had already planned to pretend to leave and circle back to catch them. But then they tell each other that they love each other and it is all I can do to not leap off the couch and knock him out. But I contain myself and continue reading the conversation unfolding in front of me. Then he tells her, "You're my girl now", to which she replies, "Always have been", ending with him writing, "And always will be".

My wife and the neighbor's girlfriend return from the movie and I ask them, politely, to sit down. I then ask the kids to stay in my son's room and shut the door. I return to the living room and confront my wife and the neighbor. I say, "So you two love each other huh?". My wife goes in to full blown denial mode and the neighbor's girlfriend starts smacking him. I ask my wife if she has been texting him, she says no. So I show her the text messages, she admits to it but says it was the first time it had gone that far. I ask my wife if she has sent him pictures, she says no. So I show her the picture, she admits it but says it was the first time. I ask her if she is having sex with him and she says no. Because I didn't wait to catch them having sex together I didn't have evidence to prove her wrong so that one stayed unresolved.

I tell her that I am leaving her, she tells me that she will make sure I never see my kids again if I do. She planned on using the fact that I had attempted suicide in high school to prove me unfit to have the children. She continues to say that it was my fault for being so busy with work and stressed out, that she just wanted someone she could talk to. Then she gives me an ultimatum to decide what I'm going to do or she will decide for me. The neighbor's girlfriend starts defending the two of them saying that it couldn't have been serious if they weren't having sex and that my wife and I are too perfect together to let this break us up. The neighbors go home and my wife and I argue for the rest of the night about what we are going to do. We go to bed separately having not resolved anything. We keep going back and forth on the subject all weekend and finally settle on we were going to separate temporarily while we figure out what we want. I was going to stay in the house and she was going to take the kids and go to her mom's house.

That Monday I go to work and I get text from her in the middle of a meeting with my bosses stating that she had explained things to our kids, but that they were upset and I need to explain it to them also. I get home from work to find my kids crying. She had told them that mommy had to move out because dad was mad at her. When my son wanted to stay with me she told him that he can't. My son put it together that if mommy has to move out because I'm mad at her and he must move out then I must have been mad at him too. My daughter was crying because my son was, I don't think she was old enough to understand what was happening.

It was at that moment I realized she was going to drag the kids through hell if I left her so I swallowed my feelings and begged her to stay. She agreed and insisted that I apologize to our neighbor since we were still going to need to hang out with them because our sons are good friends. I hate it but I do it anyway, we still hang out with them from time to time and they come to our various birthday and holiday parties. But I'd do anything for my kids and I behave civil every time.

Things die down for awhile, I still think about it constantly. I worry how can I keep from making her so unhappy that she cheats on me again. Then almost a year from the original incident, around Father's Day again, she send him pictures again. She claims it was an accident that she meant to send them to me instead. I don't fully believe her but I move on anyway.

Things have been quiet on that front for about 4 months now but I still think about it constantly. This is going to sound stupid but I feel like I have a part of my brain that I can't shut off, that is always thinking. I used to use that to solve programming problems and it made me very good at my job. But ever since this incident, the only thing it thinks about is her and him and if I did the right thing. My job performance has suffered and I feel like I haven't gotten sleep in months. I'm afraid that after this much time, and the fact that I begged her back, that to say that I want a divorce now would only make her more vindictive towards my children and I. I just feel like I have put myself so deep in a hole that I can never get back out. I haven't really talked to anyone about this. I didn't want to talk to my mom about it because I felt she would treat my wife differently and I didn't need the two fighting anymore than they already do. I tried talking to one friend about it but his advice was to put my trust in God but that was not much solace for me as I am an atheist. So I have no clue what to do with my feelings or how to move on from this.