@KISHOREPANDE,
Okay well I'll translate because the expression "go behind a girlfriend" really isn't conversational English. What I expect you mean is -- and please correct me if I'm wrong -- having a steady girlfriend.
Well, if you don't want a steady girlfriend, don't try to have one.
Really, this is not difficult.
Sorry if I sound flip but the bottom line is, if you don't think you can be faithful and treat someone right, don't waste their time. You are allowed to have nonexclusive relationships in your life, so long as both of the parties know the score.
If you are not ready to settle down -- and it's not impossible that you will never be ready -- don't force it.