My colleagues have said my boss has a crush on me. How do I deal with this professionally?

A few of my work colleagues have said my boss has a crush on me. I have to say I don't feel the same way about him. I work alone with him in the office and so do my other colleagues in their own offices, but still they've picked up on this. My boss will make comments to me like, "I see you're wearing your slinky belt again" or "You're like me - we're both long gone" (as in he's just simply picked on the fact that I do have some personal problems - not that I've discussed them with him, but he's just sensed it). Sometimes he'll give a wink at me. I have no feelings for him whatsoever. We have a laugh and joke now and again, but in no way is there anything in it on my part. Now that my colleagues have picked up on this, I'm starting to feeling so nervous