WHAT IS HE TRYING TO DO? NOTHING MAKES SENSE? WHAT DO I DO?

It's just one of those classic scenarios where two people become really close and support each other while they are both looking for something more suited to their desires and unfortunately he found her before you found him. So, he's really not your type anyway, right? Be there for him if she dumps him or if he needs you to lean on but, for the most part, he's found something with her that he did not find with you and he has been craving it all along. So, just let it be what it is and be kind and friendly when you see him. Ask about her. And, if you don't see him, just move on and find the perfect guy for you. I wish you well!