Should I say happy birthday to him?

There’s this guy I’m friends with. We used to both be interested in each other but he lost interest. The reason I’m not sure whether I should say happy birthday is because he’s the kind of guy to run away after he gets what he wants / when the girl gets close to commitment. He gravitates towards women who don’t seem to want him. This is fine but just in me staying friends with him I’ve felt a little mistreated. He would take days to reply to me sometimes and he never made an effort to get to know my birthday and say hbd to me on mine. So I don't know. I want to say hbd to show him I remembered but not if it’s going to be a grounds of him mistreating me.
Should I say happy birthday to him?
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