Quick advice.

I'm not gay, I'm probably as straight as can be. But please hear me out.My best friend pf 5 years just recently came out to me, before his parents even, and started calling me honey and legitimately wanted to make a relationship work. I told him that I'm straight and that I don't feel what he does, but we could still be friends.Now he won't talk to me, did I mess up? Did I accidentally just deeply offend him? What did I do.