Did a tumor/high testosterone make him cheat?

My WP (M, 58) and I (F, 49) were friends 10+ years then his wife died. We started dating after and have been together almost 3. He met a woman in May and has been with her since. DDay was late June. He broke up with me officially in late July. Throughout this process, he has not been acting like himself. I’ve had people say that it’s because dating someone is different from being friends, etc. But I know this man and I have seen him across work and personal situations for more than a decade and he has not been behaving like himself. He’s also been waffling on whether he wants to get back together and doesn’t consider what he did cheating because even though they had oral sex while he and I were together, and he had this emotional affair, he did break up with me before they had sex sex.

A couple weeks ago, he told me that his testosterone tested at around 1200. His general practitioner has referred him to an endocrinologist because the GP said he might have a tumor. I looked it up, and if he does, the symptoms are risktaking and irrational thinking and character changes. Am I wrong for hoping that he has a tumor so that would just explain all of this? What has been hardest for me is that he’s not acting like himself. He’s not being the man I love, and when he disclosed in June, I actually was worried something medically was wrong with him because he was acting so abnormal for him. But at the same time, I’m just supposed to erase what he’s done to me? And if he doesn’t have a tumor, if this isn’t caused by something wrong with his pituitary, he’s just an ass?

I also keep thinking that if he has a tumor, he will need me because who will take care of him after surgery? She sure as heck won’t, I tell you that.

Am I a horrible person for wanting him to be sick?