Edit: I am open to harsh criticism not here for validation. It is something I struggle with

The night I found out she cheated on me (the first of a few different men) was one of the worst nights of my life. We had just come back from a trip to look for housing for a new city to live in. 4 days later she was acting strange and said she was gonna go out and have drinks with her friend. I got a weird feeling later that night and decided to check the security cam we shared access to. Literally the moment I turned it on I saw her walk in with a man and unplug the camera. I watched this happen live. When I confronted her about it she claimed it was just a friend she met that wanted to use the bathroom. The next day I get her to spill the beans and she admits she’d been seeing the guy behind my back and that he had convinced her to leave me and cheat and go poly with him. I was devastated. She said she had this plan to tell me the next day that we needed to take a break and it turned out it was just so she could see this guy. She made me move all my stuff out and I was in tears the whole time. We cried together she apologized but said she felt some spark with this guy that she'd never felt before.

After I got my stuff out she was texting me and saying stuff like I really love you I'm sorry for doing this I wish it didn't have to be this way I miss you already. And I said well you shouldn't have cheated and lied then. And she immediately snapped back with some issues from the past. Basically I had a female friend who was 100% platonic and she would blow up about her all the time and claim I was choosing my friend over her. So I stepped away from the friend for her sake which really hurt to do but I loved her and I did it. I do regret it.

So she texts back well maybe you shouldn't have chosen her over me. I was livid and it triggered me deeply because it was such a huge sacrifice on my part that she still rubbed in my face after cheating. So I went on a huge tirade over text telling her exactly what was on my mind and all the ways I felt she'd abused me. I had lost myself and kept going and going. She started saying it was making her spiral and she threatened to kill herself. Which is something she always did when a conversation didn't go her way.

Come to find out she made an attempt to hang herself with the door knob and her friends got her to a psyche ward. She stayed there for 10 days and it was so peaceful all around and it's when she finally got her bpd diagnosis.

She still says that it was my fault she made an attempt and her friends see that way too. But nothing I said was a lie and none of it was abusive in terms of language. I didn't curse or call her crazy or anything. Just told it like it is. Months of practicing restraint with her came out in one night. Months of holding back in the face of her constant verbal abuse. And she still says it was my fault she almost died. I never ever and would never say anything like "do it kill yourself". I merely ignored her threats of suicide and continued making my points.

But what do you think? Am I to blame for her attempt? Part of me wishes I hadn't said as much as I did, but I also was in such a dark place that she was allowed to go to frequently and without apology. I have since apologised profusely and never did any like that before or again. I was always calm in the face of her splitting. I regret it but I also don't feel like placing the blame is justified