Aiyyo! I've heard of several cases over the years. The first one many decades ago when I was just a kid. Although that one was a permanent separation rather than a legal divorce. Too many marriages are held together only by the children. Once the kids are off on their own, there's no glue to hold the couple together. If ILs move in, DW decides she'd rather look after her own parents. I hear gray divorces are trending in the US: This is why baby boomers are divorcing at a stunning rate After Full Lives Together, More Older Couples Are Divorcing Grey Divorce: Its Reasons & Its Implications .