does that mean he starved Famine so much that he was weak enough to let them all go, to let the town out of the spell?

I thought he killed the demons inside of Famine and Famine didn't survive that? I will forever not know why Dean didn't just cut off the finger while Famine was distracted, though.

I don't think Dean is dead inside, either. True, he is a bit apathetic this season, but he isn't exactly walking around like an empty shell, either. If he was dead, he wouldn't care if Michael possessed him or not.