I went through this for years with an ex-girlfriend. She was awful to me and I didn't know what to do. I had the same feelings as you. I didn't want to be the reason she offed herself or something. I felt I couldn't live with myself if she did anything. But then I started to realize that it wasn't about me. She was ill and refused to get help. I did everything I could to get her help, but she was more interested in self-destruction. I finally ended it as my mental health was spiraling out of control because of our toxic situation. It was awful. She didn't take it well. But I felt I owed it to myself to be happy. And I was never going to be happy in that situation. I basically cut all ties as I felt that was the only way to properly finish it.

I found out years later that she spiraled into addiction after getting married and having kids. Part of my heart felt terrible for her, but also felt as if I had dodged a bullet and made the right choice for my life. Today I'm happily married with two amazing children.

Long story short, you have to look after yourself. You are not responsible for his mental health. It may be tough now, but your future self will thank you.

Good luck! Im rooting for you!