Dilemma ~ Do you tell a girlfriend when her husband is cheating on her?  What would you do if your BFF’s husband is responsible for one of your friend´s pregnancy?

It is difficult enough to tell a friend when you see her husband/boyfriend/partner walking hand-in-hand with another women, therefore breaking such heartbreaking news to anyone would not be easy. But is it right or wrong to let your best friend know that her husband has been sleeping around?