Well, I hope I can express this in a way that still lets you know my motives are positive and charitable.
If it was me, I don’t think I would have written it in a letter for a couple of reasons. First and foremost, it hurt your wife. If you felt the responsibility to express anything, it would have been worthwhile to try to find a means or method that would not create hurt or damage for your innocent spouse.
Second, putting something like that in writing is virtually guaranteed to create misunderstandings or hurt feelings. It is very, very difficult to handle a touchy, emotionally-charged issue in writing. The person reading it starts to get worked up and in all likelihood doesn’t even really read what you said – they read what they thought you said. There is no room for gestures, tone of voice, or body language to get the message across. If they start going off-track by paragraph two, there is no opportunity to realize you are being misunderstood, clarify any misperceptions and get things back on track.
Third, when it comes to disagreements or misunderstandings with our extended family, I tend to defer handling issues with her family to my spouse. Similarly, I tend to handle any issues with my family. For example, if my mother says something hurtful to my spouse (and she has), it is up to me to address the issue with my mother. Conversely, when we decided it was time to talk with my in-laws about getting nursing assistance for my mother-in-law, my wife was taking the lead.
Fourth, I have to assume that your father-in-law knows his actions are wrong, and violate Church teaching. He is a big boy. Did you really think he was going to leave her if you expressed disapproval? I would suggest that some time spent in self-examination to get past any possible rationalizations and truly understand what your goals and motivation were would be helpful.
Fifth, if you have children, then I really do understand the scandal issue. However, trying to draw the line between loving the sinner and hating the sin is a difficult one to draw. Unless he is a toxic grandfather who is harmful to your children, I would assume you do not want to sever that grandparent-grandchild relationship. However, you don’t want to parade the situation in front of your children as if everything is normal and OK.
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