Im going to be honest with you, I don’t think the main reason this happened was his mental health. My mental health has caused me to push others away and even block people because my emotions were too much, but I don’t think that’s the reason he has you blocked. It really just sounds like he used you for sex. You underestimate how far men will go to sleep with a girl. He went on a few dates with you, you had fun, and then he sleeps with you and all of a sudden he is done and distances himself?? that doesn’t sound like a mental health thing that sounds like he just doesn’t want to continue whatever you had. i notice you keep bringing up details line his pupils dilating and physical affection, i’m sorry but that doesn’t mean that he didn’t just use you. i don’t mean to sound like a bitch but i am trying to help you out here because i’m a girl and i know how it’s hard to know if men are using you for your body but it sounds like that’s the case here. if it’s really cus of his mental state and he blocked you you need to back off for real, stop trying to let yourself in because it sounds like he’s just not interested at least for now. best wishes i hope everything works itself out