I was in a relationship with a poly man for 3 yrs and was open to polyamory. I had a hard time because he was constantly gas lighting me. He felt strongly against monogamy and would break agreements/boundaries that I needed to feel safe. I finally cut him off 2 months ago after he tried to pull me back into dating him. Recently I started having ptsd and I contacted him & he told me that he has a new gf and has realized he is monogamous and was never poly. I feel very confused and hurt and angry.
PTSD is a serious mental illness, and people with PTSD need and deserve treatment. If your relationship with this man left you with trauma, the solution is to work with a mental healthcare professional, not to try and re-open those wounds by contacting him.
If you were able to rationalize his mistreatment of you as “oh, he’s polyamorous, so he has to act like this, he can’t help it,” but suddenly he’s identifying as monogamous, you now have to face the realization that he was just acting badly, without that salve of a pseudo-rationale. That’s painful. It’s possible he’s saying this to you because he knows it will be painful for you. But do NOT let it re-frame his behavior as something that you “deserved” or somehow brought on yourself. He was a jerk to you and treated you poorly, and whatever excuse or explanation he had at the time doesn’t really change that fact.
This guy sounds like he was, and still is, unsafe for you. Stop contacting him - you don’t need him to make sense, or apologize, in order for you to heal and move on. He can be out there in the world being wrong, and being someone who wronged you. Let that be the truth. He lied to you, he mistreated you, he strung you along - he’s the bad guy. The rest doesn’t really matter. Find someone to work with on the PTSD and let yourself move forward, not back.