Ended a 3 year relationship

I apologize if this post is a bit long but there’s some backstory to it all 3 years ago I was going through a bad divorce my ex wife was emotionally verbally physically and mentally abusing me so I ended up moving my stuff out while she was at work, but anyway a couple weeks after my divorce was finalized a friend of mine told me she wanted to get together and I agreed because we both had feelings for each other so started a rough but fun 3 years now I believe in a monogamous relationship and the way we started off was non conventional for me she agreed but only if we were in an open relationship and yea I know now that was the first red flag I unwillingly agreed because I liked her and wanted to be with her granted the open relationship only lasted a month before she closed it which caught me off guard but after that point everything was great we clicked in damn near every way we cooked together cleaned and played video games together on top of raising her at the time 3 year old daughter but up until about 2 months ago things were going well we constantly argued about having a child of our own she bounced between it back and forth for the 3 years and I felt as if she held it above my head to keep me from leaving and on top of it her daughters father was in the picture near the end of the 3 years with his new gf mind you I raised potty trained and did everything for that little girl while he did nothing and now he wants to walk back into the picture and act like father of the year but getting back on track my now ex had a job a few months ago and some of the other employees were harassing her she mentioned to me that she wanted to quit and I agreed but we also agreed that she wouldn’t quit until having another job lined up seeing as my paychecks we’re getting stretched thin trying to cover all our finances the. One day she calls me while I’m at work and says I just walked out mind you to my knowledge she hasn’t done any applications prior so the last few months she’s been sitting at home playing video games and hasn’t bothered to fill out any applications at all I’ve brought it up to her multiple times as well as her mother and she just blows it off mind you it did bother me she was out of work but she’d tell me she was going to clean the apartment and I’d get out of work and nothing would be done and one day we’re driving back from a friends house and she tells me that she wants to start being a sugar baby to this guy she used to talk to years before we met she kept talking about how she’d just have to go there shower give him a blowjob shower again and leave and he’d pay her $375every time she saw him and she kept pushing it saying we need the money I agreed we needed the money but I didn’t want her to do what she just told me about and this sparked multiple arguments I told her we wouldn’t need to worry about money if she found a job months ago like I asked I even got her an interview at my place of work yet nothing came out of it and she kept pushing the topic and insisted that it’s only a blowjob it’s not that bad but for me someone who prefers monogamous relationships that’s everything for me she kept pressuring until I gave in and while this was all going on she insisted on reopening our relationship and or making it polygamy which I was against and up until last week I was coping but when I got the call from her saying she was going to see him while I was on lunch I lost it it broke me I told her I couldn’t handle it and ended it I feel like I just lost my best friend and a daughter that I considered my own I feel lost and don’t know what to do