IIN that I can only orgasm if I imagine my boyfriend with another girl

I have the same issue! In fact I'm lying in bed feeling so disgusted and hate him and myself for shit we just talked about to make ME cum. I want it to stop. I want to be normal! I married my husband when I was 16 and I'm now 35. We've been together for 19 years. I honestly hate myself and my body. I feel like the only reason I say what I say and make him talk about other women is because I don't like myself. I feel like If I'm disgusted with myself he is too because of the type of women he likes that I look nothing like. Idk I guess I'm glad I'm not the only one I just worry I'm going to make him do something like have a three some and I'll never get over it, leave him and blame him. :/ I need help I know... coming from a family where no one has been faithful I'm any marriage has affected me more than I thought. Thanks for reading