I love a girl even planing to go for her introduction, but I can stay without her and even live without her but I always have the urge of having sex with her, but when she finally give to me and am done I started blaming myself what can I do to stop this sex urge

Stop? If you feel bad sleeping with her, surely you stop sleeping with her, not keep reasoning with yourself when you have the urge and then try and find solice after?

Keep your pants on. Keep her clothes on.

It's easier said than but this is the jist of it;

JUST DON'T DO IT.

It's hard but just stop yourself and walk away. You're probably hurting her more than you think.