Thanks for query,
I think you have undergone Lithotripsy
before 6 years & not ultra Violate operation.
Usually Lithotripsy Procedure does not affect soft tissue
You may have developed urethral stricture
due to your stone that will creates problem while you pass your urine.
Sex enjoyment has nothing to do with your urethral stricture.
A dilatation surgery will solve your problem.thanks again