How much time should you give your bf/gf to seek help for anxiety and other issues while you're doing the same to improve everything?

Back story I suffered massive TBI and still suffer from mild cognitive disorder when I was 28. To today: I've been in therapy since the injury in 2015. I have been doing DBT, EMDR and now starting neurofeedback. These new therapists have already done more for me in 2 months than some other therapists have my entire life.

My boyfriend has MASSIVE ocd, anxiety issues, issues from his step dad and how he treated him. He is stubborn refuses to take fault and draws up whatever excuse he can to shape things into my fault or other peoples fault.

We butt heads all the time because of it. Granted I have my own issues and some days I just wake up funky and moody or whatever the case is depending on how my brain feels so I'm not innocent nor will I ever claim to be a non issue.

I want him to seek therapy and meet me half way. How long should I give him. Everytime it's brought up he shrugs it off and tells me why should he if my therapy isn't working (it is). He also feels like the therapist would tell him he is wrong which no therapist worth a shit would EVER say.

I can tell that the better and more aware I'm becoming at recognizing when an issue arises that I'm starting to get the itch of this 2+ year relationship is headed towards not being because of his inability to seek help.

How would you approach the conversation and should I put a time limit on it?