Your family covered it up. Thank goodness you were not married and had children when this happened. Frankly if your fianc e could do this, your relationship did not have a good and firm foundation. It is better that it happened sooner than later. Your family cover-up is very sad.
People usually cover up unpleasant news because they hate facing the consequences.
Obviously, your family doesn t work well with relationships. You were very hurt. In relationships people do get hurt and move on. However, this past issue has cut your family in two and now they are placing the blame on you and your wife. Your family wants to close this issue, and no longer deal with it.