it takes two people to make a marriage and it takes to people to break it. Your H deciding to have the affair was his sole responsibility. But up until that moment, the R deteriorating to a point that he was vulnerable enough to make that decision, you did play a part in.
While this is true (dual responsibility in marital deterioration) for some affairs, it isn't true for all. In the book Fearless referenced by Frank Pittman, there are categories of affairs indicating some of the differences.
There are marriages in which hidden infidelity began before the flowers in the wedding bouquet wilted. Before the betrayed spouse had the time to contribute to a marital deterioration.
There are also philanderers, romantics and the love junkies who are chasing the chemical rush of new love which can't be sustained in longer term relationships. There are mental illnesses and personality disorders that crop up after marriage that contribute to the ranks of infidelity - again with no connection to the betrayed spouse's actions or inactions.
Even after the discovery of an affair, the betrayed spouse is often willing to work on the marriage in spite of the affair. The unwilling party is usually the infidel.
I don't think that it takes 2 people to break a marriage in all affairs/divorces. One determined spouse can destroy it alone.
