I have the same jealousy, morbid jealousy. but mine is different from the subject that has been told in health sites or books. I don't think that my partner will cheat on me, but I'm afraid if he finds some other women except me beautiful or attractive. He says he don't because he loves me, I sometimes belive in him but I can't stop asking questions and whenever I question him, his answer evokes another question in my mind. or sometimes I realize a conflict between his current answer and previous answers, so I feel the intense need to ask another question about it. this process of course destroys me, him and our marriage. I know questioning, over-thinking, limiting him etc. are nonsense but the psychiatrists also tell me that my expectation to be the only beautiful one for him is also nonsense. but he is the only handsome and attractive man for me, I can feel that way, so why won't he feel this way? It is possible and I don't agree with the people who tells me that. why I can't believe him is because of him being a male and his conflicts in his answers.