Why does it make you depressed? Yea he's annoying (to say the least) in his public persona/comments, but he makes damn good music. There aren't many people out there who would deny that College Dropout is an amazing album.
If anything he's putting himself in a dangerous position by being an asshole to everyone. Right now the music media gives him a lot of respect due to the quality of his music, but once he fucks up they'll be waiting in the wings to crucify him.
I can't wait for his next album (Graduation). It should be awesome. The last few beats he's done recently are very layed back, not so sample reliant, and not overproduced. For instance, the two songs he did on Nas's new album are both great.