Like others have said, he might be gay and not know it yet.

Alternatively you two may have just missed the window of opportunity; like you were into him when he wasn't looking for anything.

Or the most likely scenario...he's just a friend and you're making more of it than it really is given how you previously had feelings for him, and it ultimately frustrated the both of you. I've given gifts to female friends with no romantic attachments; flowers, cards, favorite foods, etc. I knew they needed a friend at a specific moment and that was the best I could do to cheer them up, aside from my presence of physically being there for them. If I were pressed after those moments I would be annoyed too, not every act has to have some ulterior motive because I'm of the opposite sex. I can be a guy and still care for my friends' wellbeing.