He sounds ADHD; Lack of restraint in responding (responding or saying things without thinking of the consequences first) If he is ADHD, he will probably continue to have these problems, and as these experiences build up over time, most people with ADHD suffer from depression. I have ADHD, and I have said things or acted on impulse, and then found myself shaking my head later, utterly confused, thinking, "Was that me?" and "Why on earth did I say that, or act that way?" Ask your "lost friend" if anyone has ever mentioned that he might have ADHD, and let him know he hurt your feelings, and owes you an apology; only if you are comfortable talking to him; That gives him a chance to own up to his actions; and if he doesn't, you're right, it's his loss!