BPD ex (mother of my children pregnant with new fiance)

[Gaff55]

Okay so basically I thought I had found the girl of my dreams. After 7 minths she was pregnant with my twins. We have now been broken up just over a year, she is pregnant and engaged to her second bf of two months. When we were together she was undiagnosed, I just thought she was evil. It ended when she started partying all the time when we had to young babies at home (probably cheating as well). I gave her the ultimatum to get help or get out. She got out and proceeded to try to ruin my life when she wasn't hitting me with the occasional love bomb. She is getting help now (therapy and meds) for herself and her new bf) she seems to be improving. I can't help being bitter because I was SOO good to her and she refused to get help for me. Every trip we went on together, every spot we used to eat, all our pet names,  inside jokes pop on fb, but of course with him. It hurts because I do love her. I also didn't know anything about bpd and probably did everything wrong. When she got crazy I would immediately say were done. Sometimes she would go out of her way to do things I liked but she didn't just to spend time with me. But I started to be disrespectful because i was so broken from the insults, physical abuse etc. Of course I'm wondering if she really loves him and if history will repeat itself with her new fiance. She wanted to try to make things right until she met her fiance., but I got laid off and could not support her financially and my roommate wants nothing to do with her. He moved her and both my kids in after knowing her for a week rent free. She told me she wasn't into him but couldn't mess up the situation for herself and the kids. Its so painful because we love each other but did zero of the work to make things right (she refused) I think she finally got fed up and tired with herself. I wish I could forget about her and forgive her for the hell she put me through but I can't. I also love her. Please help. I am brand new here. I GREATLY appreciate it.
ps. They have only been together 5 months.

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