I agree with Kaliope.

The guy, even if unmedicated, should be monitored. Someone prescribed him Ambien but it doesn't seem to be the case that that MD thoroughly examined him. I don't take Ambien but I know that it is a serious drug, but is not sufficient for him since he adds Advil PM, and that may mean that he is trying hard to suppress mania. I certainly don't think that he could even be called unmedicated. No, he is self-medicating by mixing an OTC drug and a prescription drug. Plus anabolic steroids. Plus alcohol. If it is at all possible to get rid of him, I think you should do so. Tell him that you have changed your mind about the girl at the gym. Tell him that you have given the matter a serious consideration and realized that you, unfortunately, can't support him in his passion. You find repeated mentions of his looks dumb. Plus, you have tried to develop an interest in listening about how much weight he is lifting, but failed. You realize that you cannot give him what he deserves (admiration and awe) and sincerely hope that the girl at the gym, since she was excited about his workouts, would be a far better partner for him. Ciao (ie good riddance but do not say it out loud).