Lack of sensations

53 year old gay men here. I’m into a monogamous relationship for the past 25 years. My partner”s long lasting low sex drive is increasingly frustrating for me, which is why I decided recently to experience sex with other men. This is a challenging period for me as this is unbeknownst to my current partner. Guess what? ED! What surprised me is that I don’t experience pleasure being rimmed or being bottom. I know this has to do with performance anxiety, and I am hopeful that everything will settle down one day. However, I would like to hear from you folks: have you been through something similar? Any insight is appreciated!!