Aww Ben is the most understanding bf ever. I love him. But really, it's time to grow a backbone. And that goes for Michael, too.
"Let's just hope Michael wakes up and realizes he's just a substitute for Justin."
Compare the way things are now, with Brian missing Justin like crazy and turning to Michael to fill that void, to back in S1, when Brian and Michael were fighting and Justin was the substitute. Justin has really become the most important relationship in Brian's life, and Brian clearly is not dealing well with the loss of it.
I don't know what to make of Michael's behavior here. I don't think this is all about just going back to the old days with Brian. He does want to be with Ben and move forward. But he also feels an obligation to his friend, and I think a small part of him really doesn't mind having Brian need him again. But this isn't doing Brian any good, and it's only hurting Michael and Ben's relationship.