Should I wish my friend happy B-day even tho he inexplicable stopped talking to me a few weeks ago?

I've been friends with this guy for several years and he's been going through alot lately (more accurately, he's been putting himself through alot lately) and a few weeks ago he quit talking to me and I don't know why (although I have my suspicions that he's done some things that will hurt me incredibly bad when, not if, I find out about them). His birthday is coming up and throughout our friendship I've never missed his birthday. I'm wondering if I should send him a birthday wish or if I should just leave him alone since he's not talking to me anyway.