vaginapagina | Can't feel pleasure during sex, too busy performing. Advice?

I was raped when I was nine, and now as an adult I can't feel anything during sex. My abuse lasted several months and I learned to kind of "switch off" while it was happening. My fiance is the first man I've ever been with as an adult, and we are very sexually open. We have tried everything together and he is willing to do anything to please me, but I can't climax during any kind of sex act. I have been faking orgasms every day for our entire three-year relationship. When I masturbate, it's so hard for me to focus and it takes such an incredibly long time for me to reach orgasm, because there is such a disconnect between that part of my body and my mind. During sex it's even worse and I feel pretty much nothing. My main problem is that I am so focused on his pleasure that I just can't feel anything in my own body. It's like I am stuck in "performance mode". All I ever think is "how is this feeling/looking/sounding to him". It doesn't matter how much I try to focus on my own feelings, I just can't, I don't know how to stop performing. All I can think about is how the experience is for him. My abuse has left me with this awful feeling like I am only worthy if I am being sexually desired or giving sexual pleasure. I feel like I have to give him the best sexual experience of his life every single time and if it's not absolutely amazing for him then I am worthless and he'll leave me. I know that's not true but it's hard to make my mind believe that. I don't know how to turn it off. Even when he is going down on me and it should be entirely about my pleasure, I am still only thinking "does this look/sound sexy?" and I fake an orgasm pretty quickly because I feel like if I didn't I would be laying there for literally an hour before I actually came and he'd hate be miserable. I just want it to be great for him. I feel like the only way out of this is to be honest with him and tell him that I have never had an orgasm with him, but I just can't do that. I've been faking for three years, it's gone on too long, I can't just straight up tell him it has all been a lie, I'm too afraid. Is there any other way to approach this? Does anyone have any advice on connecting with my body, feeling pleasure, being in the moment? Is there a way that I can ask for things like more foreplay without either hurting his feelings or coming clean about my lie?