This red flags started popping up pretty much immediately after that. Pretty classic emotional abuse - using my insecurities against me, passive aggressive jokes, etc. I tried to bring up the issue, but it continued. I revealed to him my past history of rejection and bullying in childhood, how I had very few friends, etc. He began making comments about my personality (I am too loud, too excited, etc) and suggested his friends who met me were unimpressed and did not like me (find me annoying). Yet conversely he tells me that he likes me for who I am and to just be myself. However it seems like being myself irritates him, and it seems like he doesn’t particularly like me. I expressed this thought to which he replied “your trainable” “I can change you” but also that I shouldn’t expect him to change.

That sounds like the guy's problems. None of that behavior presents in PTSD. I don't know your situation, so I'm not trying to provide relationship advice, but I am a combat vet. I know a lot of other mentally messed up people that have a similar background to my own, and I don't think anyone would try to blame being a jerk on PTSD.