You have experience 3 times with this girl so that must be a huge step for you ...
Maybe what your friend should do is have you massage her from head to toe so you have the control of that you touch and what you don't want to touch have you done a full body massage on her ?

If not try that then when you feel ready take one piece of clothes off her one at a time and over time have her be nude and give her a full body massage.
Then when your ready have her do that with you a full body massage .
Once you feel good about that then try something else ..
I think your obsess with being a virgin like you think your not clean if you go all the way with a girl .

If you don't feel the need to have sex then don't , not everyone wants or needs sex to be in a relationship . Just be honest with people you date and say I'm not into sex .
Maybe you need to fall in love to have that special connection and be married , so you feel clean ?
Could that be it ?
Don't feel like you have to have sex because no one is pushing you your putting that all on you .
Do other things in life that make u happy why let sex be in your way of happiness ?