Ex got dumped, contacted me after a year of acting like I don't exist?

That's basically it...he has ignored my attempts at staying in touch for the last year, and now that he's single (and lonely) he wants to hang out. He acted as thought the last year didn't happen...and as if our break up didn't smash my heart to pieces. I've moved and I think he should too...as I already told him I don't have interest in hanging out again. Why do exes do that though? Why would he think I'd actually want to hang out?