Hmm, did it ever even enter your mind after a 3 year relationship and how much effort he put into his education (medical studies are HARD), that you could have gone to his graduation so he could have someone there who was "proud" of him? Did you ever show any excitement about the fact that he "finished and was receiving a diploma?".

YES, ADHD is a challenge, especially when it comes to learning and getting a degree. Maybe he wanted sex, and maybe he wanted "more" than that.