Not normal but I deal with the same thing. My ex mulched my entire yard a week before moving out. She’s the first to text me happy birthday, Father’s Day etc. Heck she spent more on me for Fathers Day then she ever did while married. Many other examples. How do you deal with it? You shrug your shoulders and keep living the single life. If she changes her mind you’ll know and then YOU get to decide how you want to proceed. Some of them do feel guilty about blowing up the family and some want to keep the road home smooth just in case the grass isn’t greener.