He didn't flat out say any of that shit. He said he was powerful and he lost his power because he tried to gain mystras favor(which is a no no to mystra). Sex with mystra is in his head, she didn't ignore him so much as he wanted her favor etc.
He did. You saying it was in his head means he told you about it. You are choosing to not believe what he says. And in 6 playthroughs he said all that ONCE. You have a false assumption that you have had every possible conversation with him. Your experience is not other people's. If you are this vehement about it, you obviously didnt see the text I did. You're just choosing to not believe something because you personally haven't seen it. Hubris.