Relationship/mental health advice needed asap

Hey y'all,

I'm gonna try to keep this short because it's late and I need sleep! Long story short, my boyfriend and I, throughout our relationship, have had a lot of arguments over things that upset him. I always try to be respectful and see his side of things and try to make it better, but lately I truly feel like he overanalyzes any little thing I do that upsets him and turns it into a big argument over what I did "wrong".

Now, my bf has a history of self harm and I'm sure depression, and he has been cheated on by every girlfriend before me. No doubt he has been through shit, and he has never sought help for his mental health because he says he doesn't need or want help. As touchy as it may be, I really want to help him see that he does need counseling to be able to deal with his emotions and live a happier life.

We just had an argument tonight because after we swam together, I stopped by his apartment to grab something I left and said I would stay except I need to go to sleep soon (we live in the same student housing btw). Later he texts asking what I'm doing and I say I was just eating a snack and watching youtube/relaxing before bed. He then got upset that I was doing things that "aren't important" when I could have stuck around and spent time with him (it was 11:30 pm by this time).

We're going to talk about it more tomorrow, but if anyone has any advice on how to gently push someone towards getting mental health support, I am all ears! I really don't want it to come off as me blowing off my mistakes (because I definitely have fucked up at times) by saying he has a "problem" or whatever. I genuinely just want him to realize that he does sometimes blow things out of proportion, and that along with his history are very valid reasons to seek help.

Sorry this was long anyway, but major thank yous to anyone that read fully. And btw, besides our arguments that we have, yes, my bf treats me wonderfully and I do love him and love being around him. Just a friendly disclaimer :)