You are not alone in this dilemma. Not knowing you, I can’t give you a definitive answer but I can tell you this: Usually the root is in the past. In some families and cultures, women are divided into only two groups: “Pure” or “whores”. Pure women are to be worshiped and loved but are not sexual. Whores are sexual but aren’t women to love. Nothing could be further from the truth, of course. Loving and lovable women do like sex. Women who enjoy sex aren’t shameful.
If that idea is anywhere in your history, it is still being played out in your present life. If your issue stems from some other life experience, it can still be changed. Going for some therapy can help people reconsider early lessons and make new adult decisions about their beliefs, values and behavior.
I hope you will see a counselor to free you of the problem. You deserve to have a loving relationship with a woman that includes the closeness and pleasure of sexual intimacy.
I wish you well.