I'm just throwing thoughts out there and who knows so I apologize if I am wasting space and time.
When it comes to sex with someone I love, I have a need for connection to perform. Let me be clear in my reference to connection; I don't feel it as a sliding scale for me...I am there or not. If there are any negative influences or issues I simply can't function sexually because my connection is broken in that moment.
Connection can be broken by things happening in my partner's life or in my feeling undeserving to touch the person I love because I say or do something that hurts or worries them.
I've had casual sex and one night stands where I managed to perform but it was not easy and turned me off of that activity.
Physiologically I have much more need for connection with some one I love than for some one I am essentially just getting off inside. There needs to be a sense that more than our bodies are going to touch...something deeper needs to be shared.
Is there any possibility that there might be an underlying sense that something is not quite as right with your relationship that might be generating this issue for you? Maybe it's not trust that is causing it but an unidentified concern or denial that makes you unable to have sex with those you love?
Just my thoughts
Playing the Game of Life with Monopoly rules.
Monogamy might just be in my genes
Poly Events All Over