The issue seems to be on your side of the fence in determining if you: want an arranged marriage, are ready for marriage, and if you can cope with your unforgiveness of him.
Let’s take each one of these in order. If you are saving your virginity for an arranged marriage and in the next sentence start to talk about “sleeping around,” then you’ll continue to bounce back and forth between these conflicting motives. You might first want to sort through what is important to you, what is a priority personally and culturally. Often this type of inner contemplation can be facilitated by individual therapy. The Find Help tab at the top of the page can help you locate someone in your area.
Secondly, the question of readiness for marriage at this point in your life is reasonable and important. As you begin the journey of self-examination in therapy you may find that this readiness question is fueling the saving yourself versus experimenting options.
Finally, it is interesting that you were drawn to your boyfriend knowing his history, thought it was okay (or that you could cope with it) only to find out you are not. My best guess is that this concern about his history, as well as the saving yourself and experimenting, are conflicts emerging because you are questioning yourself about readiness. Of course, this is only a guess and some individual therapy should help sort it through.
Wishing you patience and peace,
Proof Positive Blog @ PsychCentral