Relationship issues

Okay so my boyfriend is currently locked up. He's been locked up for about 9 months now. Me and his grandma has been the only one doing all these things for him buying him everything he needs, going upstate to see him and all this stuff. He has this person he considers a "bro" that I don't particularly like anymore and I feel like he's always defending them even tho they don't do shit for him and it's really starting to get to me. I don't know how else to deal with it because we always ending up arguing when we speak about it and when I tell him I prefer to not bring it up because it's always the same outcome he still gets mad. Honestly don't know what else to do but cry. I would like to just leave but it would be two years down the drain and I feel like I just can't walk out of his life. It's such a confusing and frustrating feeling. 😢