It’s not me, it’s you.

Okay so i’m going to try to make this as short as possible. Me and my bf have been together three years on valentine’s day, and i’m not getting what i need out of the relationship, we moved into an apartment together and i just wanna leave, i’ll send him money to pay the bills and whatnot but i don’t think i could go another day without telling him how i feel. I’ve practically had to beg him to treat me right and now that is is after the fact that i begged it means nothing. How do i sit down and talk to him about it without him blowing up at me?