I don't know if there is a pattern when it comes to "In-Laws", but when we were married my ex-MIL lived with us for 12 years. Ex-MIL saw how I was to her daughter. During those wonderful years I was the better of the 2 son in laws as she always express it verbally in almost every occasion or family gatherings. When ex-Wife went into the tunnel the only thing she can do to get people on her side and to agree with the divorce is to accuse me of being "sexually abusive" to her. Obviously the only place that the ex-MIL could not be with us is in our room, so instead of trusting what she has witnessed in the 12 yrs and trusted how she viewed me, she immediately agreed with her daughter and encouraged her to file the divorce. Take note: I tried defending myself to my ex-MIL, I told her there was something really off with our "Male Guests" who was an old suitor of my ex-Wife when she was in High School that I allowed to stay in our house for the Labor day weekend. Guess what. ex-Wife's current boyfriend is indeed that Guest that we had, yet ex-MIL didn't even reach out and say anything to her daughter. Ex-MIL up to now treats me as if we've never met. So now in my ex-Wife's family, and new set of friends I am just an ex-Husband that sexually abused her. What's funny though... when she filed the divorce she couldn't even put on the "Reason for Divorce" what she is accusing me of. So for my situation you can definitely place one under the column that says "Yes in-laws affected the outcome".