How to I get him help? *TW*

I'm just going to jump right in.

My boyfriend, whom I've been with for almost six months now, is suicidal. Last night he almost came close to doing it, but last night he also told me he's giving life another chance. He's giving himself till next Saturday.

I know you'll all say "get him some help" but from who? I haven't met his grandmother, so I can't go to her, and I'm not in any contact with any of his friends. I asked if he'd go back to therapy, he said no. I've never been through this before and I'm lost. I can't leave him, I don't want to give up on him, but staying is making me hurt more and more.

Can anyone provide some sort of advice? I want to help but I don't know how.