I think it's the opposite. Alex is definitely hurting. The cold play/rejection is hurting his pride and his feelings. He's aware that this is the DG he wanted in the beginning, but the DG he got is the one he misses. He just haven't figured out that the reason he likes the first DG is because that one wasn't just a casual partner but someone he actually interacted with on a personal level. Everyone else got the mask, but DG was around to see how ugly he could be. MD doesn't count because Alex and MD's relationship was forced and competitive. You're right though, Alex is emotionally slow and that may have a lot to do with his past trauma. The guy that he used to like was probably his only crush and after being betrayed in some way, he figured that the entire gay world is not meant for actual love. He wasn't trying to look for it because of his job and I'm guessing that DG is initially not his type. We tend to fall for those who are not our ideal type
I wish DG would reject Alex outright!
Instead of agreeing to sex so easily..... Alex is an emotional retard, who can’t admit his feelings and this sex actually hurts DG more than it hurts Alex
(づ￣ ³￣)づ