My(26F) boyfriend(25M) cares too much about the wrong people

My(26F) boyfriend(25M) Ty is a wonderful, sweet, and compassionate man who always puts others needs before his own. He's selfless and cares so much about other people, and that's a thing that I really love about his character.

However, as of lately, he has been putting himself down. Last month, his mother was messaging him about things that were happening in the house while Ty was away hanging out with some friends with me. We all decided it was best to call the police for a welfare check on his mom, and spent the night at this friend's house for safety. During all of this, Ty was withdrawn and overwhelmed as well as unsure what he wanted to do because he constantly gets conflicted in stressful situations like this. I was trying my best to support him and tell him that this was the best option since this man has been abusive and a drunk for as long as his mother and him have been together, but Ty would just shut down.

I should also mention that Ty has ADHD and gets medicated for it, but still finds it hard to function during stressful events and easily gets overwhelmed in crowded places etc.

Anyway, when the police were called, they showed up and had reasonable cause to arrest the abuser and remove him from the household. It has been about 3 weeks since then and he still hasn't returned, which I'm glad for because they've had some peace in the house for once. But Ty had said to me that he blames himself and mentioned that he didn't want to put the guy through all of this since he always tries to see the good in people. I got a little annoyed and explained that it was the right thing to do because he is constantly making him and his mom fear for an outburst and they would have to walk on eggshells not to make him upset. Ty says that he knows, but he still feels bad since this guy is now in a hotel room that he can't afford because he was told to stay away and all that, but I told him that it was because of his own actions that he's now having to suffer the consequences.

I'm not really sure how to go about talking to Ty about this. I've already stated over and over again that he shouldn't take responsibility for other people's actions, but it was all in how he was raised. His family was never supportive and when he was younger, he was blamed for everything since he was the only boy with 3 other sisters. The grandmother the lives with them hates men and has always been abusive towards him verbally and emotionally, so he's got a lot of healing to do when it comes to trauma. I understand his positioning, but I want to better help him work through it like a partner should. If anyone has been through this kind of thing and had to help someone overcome fears, anxiety, and trauma, any advice would be appreciated.

I love this man so much, with all my heart. I care about him deeply and it hurts me when he's hurting and feeling conflicted. I try my best to comfort him, but he's scarred from what he's grown up with and I don't know how to really help. I don't plan on leaving him, so breaking up would not be a good suggestion for this post. I'm not experienced with trying to help in this type of scenario, and I almost feel like I'm not actually the person that he needs, but I really want to get him on his feet and stand up for himself while also keeping his compassionate side. I know it will be a long time before we get there if I can help him better himself, and I'm willing to put in the time and effort, but I'm unsure how I can go about it..