Wow...just dont know how to feel

Its a very long story not sure if yall would be interested in listening to. I've been in a marriage for almost double digits.

A couple months ago I rekindled with someone who I consider a "soul partner". You ever meet those people that everything is just natural? No masks no games just bluntness and ease of being around? Like an old friend or coworker that came back from vacation? But deeper. Its hard to explain. Someone who truly understands me. However stupid it sounds we were "ride or die" we trusted each other. There's alot of history behind us that has deeply connected us. Just...complicated I guess.

We started by external forces having to be side by side with each other for an extended period of time of the day. We were exceptional together. Timelines getting done sooner. Everything smoother and easier. Things got blurry after a while. Around the holidays we started unintentionally flirting without meaning to. Arm brushes. More unnecessary closeness. Both of us have multiple year partners. Partners with futures with. I can't speak for them but me and my partners relationship had been deteriorating for a while. I still consider them my best friend but I'm not sure where we stand in the relationship sense.

2 weeks ago she had informed me that they were on their ovulation cycle and were feeling some way. By this time I had tried putting a stop to it as we both had partners and commitments but reluctantly agreed with them that we'd always be bonded to each other. While leaving the project and driving them home we pulled over and had very spur of the moment unprotected sex. When we're together we just...its as if the world just exists between us. Either way a couple days later they ended up being distant. Went from daily communication to every other day. I just thought it was them arguing with their partner or such. When I met them again they pulled me aside and we had a deep conversation. She was late and wasn't sure who the father would be. She wasn't having the child nor was she telling her current partner. She physically can't or its basically a death sentence for either or both. She was inconsolable realizing what she had to do if it ended up coming back positive. I supported them as best I could. Whatever they needed anything I did my best to be there for. I knew they were not in a good headspace. They questioned their fitness of being a parent. Of course they would be. I tried consoling as best I could. Just sitting with them and just listening. The day is coming shortly of what needs to happen.

I'm now processing all this and I don't know how to feel. The fact that they're in pain because of a stupid mistake we did. Us both wishing and thinking of what could have been. I guess I just needed to get this off my chest as well. I...just don't know what to feel now. I'd love to hear if anyone has had similar situations and how they lived through it. Thanks for listening.