Is the therapist working with you on changing your perception on what sex is and isn't? That it's not dirty or sordid, nice girls do have sex, nice girls who you would be interested in would want to have sex with you, and that isn't any guilt involved. With your history of sexual abuse, it's not a wonder that you feel as you do, I'm not sure you can consciously help it.
You'll get there, it's just going to take the right woman... You just haven't met her yet... but you will... (We like cute faces