I think I love one of my closest friends
Do you think he wants something with you?
No, I think the dude is just blowing hot-air.
Since you seem to think he isn't serious, it would not be okay to risk a friendship for a relationship that will not last. It is better to have a friend rather than a short relationship.
But maybe he's not hot-air. Maybe he just doesn't show his feelings.
If you are not sure, maybe you should risk your friendship to have a relationship with him. You might end up with no relationship at all if you persist.