Wow, I really feel badly for you. That is horrible that you feel that way. Too many people in the western world have horrible self esteem namely due to what the media portrays. Of course, in your instance it isn't what you see of the covers of magazines at your local supermarket, but I'm sure you've seen porn where everyone is perfect and has a 12 inch penis. Trust me when I say this is not normal. The average penis size is probably a lot smaller than what most men believe. In my experience 8" or more is more rare than 5"... and honey, when I was younger I was a slut, and now I'm a swinger (yes, there is a difference ;))
However, based on your post, I don't think that anything anyone says here will really help you. I think you need to seek professional assistance. And I don't mean to a surgeon, I mean to a counselor. It sounds like you really have a self image disorder that can be effectively treated by therapy with a licensed therapist.
Make that call, as embarassing as it may feel... that is really the only way to allow yourself to have an enjoyable sex life again. Keep us posted.
