I don't think Bellamy considers Finn his friend though; his relationship with Clarke (and to a certain extent, Raven) has developed from antagonism to a sort of friendship/mutual respect thing, but I don't think the show ever really gave us an indication that Bell did more than tolerate Finn because well, "his people"…

Definitely wasn't pleased with the way they were blaming everybody but Finn for the massacre but I took it as the sort of grasping-at-straws reasoning that desperate people are wont to do. Like I think it's easier for Raven and Clarke to blame Murphy than Finn because Murphy's always been abhorrent to them. Raven…

I forget the exact episode, but Raven mentioned something about her mom trading her rations for alcohol. She got together with Finn because he'd split his rations with her.