Singular partner’s past affair

This sensitive issue has been broaching in my mind for quite sometime. Many of my pals use this as an excuse to get me also involved in their ‘playboy fun activities’, which just doesn’t convince me, ever, to get indulged. The issue of ‘fun’, notwithstanding all the open views i have about it, (and with due respect to taboo-ic rejection of the thoughts of free love for all) a beloved's past affair is a psychological upheaval. I think there probably still exist a positive answer to handling the case of one the partners' past afair when the other is innocent.
I often think that if sociology and social psychology ever were a subject for the IIT entrance test, the JEE, then this question of handling singular partner’s past affair would have aptly judged people’s mettle. Not all people can dare to think of this situation and worse enough, try solving it in a constructive way. Self-annihilation seems to be most tempting solution. Of late I have started feeling that there still exist some good solutions to it, because life definitely has solutions of such cases. Therefore, all that the people need to do is not to get bookish and watch this world with an open mind.
To get my possible hints to the solution , I turn back to my favourite place, the movies, which deal with such topics. One of the flicks I recall is one slower one ‘Dil kya kare’ and another one, “Mrs and Mr Iyer”.