In your opinion, is it alright to seperate the art from the artist?

This is coming from a big Kanye West fan. I think he's an incredible artist and would defend a lot of the controversial things he's done until this year. However, starting with that time he tweeted "BILL COSBY INNOCENT" to all of his impressionable followers, I've found it more and more difficult to justify his actions. I'm still a huge fan: I'm going to see him for the first time in September and honestly couldn't be more excited, but from time to time I do feel a bit guilty about financially supporting him.

So, yeah, basically I just wanted to ask everybody the question that's in the title. Is it okay to seperate art from the artist, and if so, why?