I'm so sorry
My dw had an affair when our twins were 18 months old and it was awful. I felt so alone and unprepared and was just terrified about the idea of being a single mom. I couldn't even think about what it meant for our relationship, I just kept imagining our family broken up and it was devastating. After getting over my initial shock and horror, I realized that I wanted to make things work out. I wasn't going to leave dw over this. I told her to come home (I had initially asked her to leave), and she did, but she told me it was fine that I didn't feel the need to end things but that she wasn't ready to end things with the other person. I was like WHAT?!?! I never imagined that I'd have to be in the position to sort of "win" my wife back.
I ended up doing a lot of self-reflection and thinking about how even though my dw's affair had originally come as a huge shock (we'd been legally married 3 weeks before), I could also see how it had happened. We'd been so focused on the pregnancy and then having babies and then having toddlers, and we had completely neglected our relationship. I also made myself realize that all of the things dw was experiencing in her affair--a new relationship and all the excitement that it brings, the way it feels to kiss someone for the first time, etc.--were very appealing things, and that they were clouding her vision. So I decided to forgive her for losing herself in it a bit.
I also did a lot of thinking about polyamory and tried to figure out if it would work for me. I decided that under certain circumstances it could. That helped to give me a different way to look at the affair, and also made dw feel less trapped (although we haven't yet ever had an open relationship, we do talk about it).
Ultimately, we decided to work really hard at making things work. In order for things to work we:
1. Had to individually both be happy (in work, with friends, etc.)
2. Had to make time for a kid-free date night once a week
3. Had to promise each other to give it our all for 3 months
Dw ended up getting a new job and that helped tremendously with her own happiness level. We also moved to a house where she was a lot happier and where we could have more personal space (we'd been living in a huge studio apartment--one big loft without any rooms or doors). We started having our weekly date night, and we didn't talk about the status of our relationship, we just focused on loving each other.
It worked out for us in the end. Eventually we were able to learn from the experience and grow from it and be stronger for having been through it. But it definitely took time. I would say that it was 6 months before I felt totally committed to dw again.
Pregnancy is such a vulnerable state, and I can't imagine what it would be like to go through this in the first trimester. Please know that we are here to support you.
So many hugs,
Lex