Husband cheated with a coworker!! Now living with her 💔🥺

After 12 years and 3 children my husband cheated, got another woman pregnant, and walked away. They barely met literally started talking for about 2 months and she got pregnant. I am in a deep depression, literally feeling suicidal some days. I had to stop taking my antidepressant medication because it was making it worse. And got put on another medication. I put a protection order on him because he was literally abusive. I feel like its my fault in a way because I know I was a naggy bitch. We have just been through alot but we also got together very young. I have high hopes he will come back, I miss him, and love him unconditionally but he has made it known he is "happy" then again he tries to come to my house and "do things" with me. Will he ever change? Do men ever regret? I filed for divorce and he never signed the papers. Its been 3-4 months now since I found out. I just wish I knew why he did things the way he did.. how does someone throw away everything just like that.. Praying to God for a miracle 🙏 ☹💔 I feel like I need help and I'm too emotionally attached, does it ever get

better? I wish I knew what she has that I don't.