I don't know anything about this.
Really I don't! (I've been impotent for so long I can't even remember what sex was like.)
(There's actually a joke related to this I can share here. Two old men are sitting on a park bench. One of them elbows the other
& says: "Hey, you gettin' anything on the side? The other replies: "Why... I haven't had anything in so long, I didn't even know they'd moved it!"
The only thing I can say is that I've been told some psych med's can apparently cause a man to have an erection he can't get rid of.
I don't know if you're on any psych med's. But if you are perhaps this is a med-related issue that is spilling over into your sexuality & mental-health-related issues? It may be something to consider.
My best wishes to you...