Because there are 3 sides to every story Chickie. Yours, Mine, the truth. We all add our own perception to everything that happens to us, every single day. Example I was working one night, we had a woman jump off a bridge, it was reported by at least 10 different passers by. Every single one gave a different description of the clothing the woman was wearing. As different as Jeans and a halter top, to a little black dress.
You read over there about women with problems on the "other side of the fence", then you judge them by your own situation, adding your own perception to what they are saying. Those daughters in law, are not your daughters in law. What they say, in my opinion, is no better/worse than anything you have said here. Different but not worse. My Mother in law thinks I stole her son, or My mother in law thinks I am a gold digger etc, have been around forever.
Yes there are some new terms like emotional incest to describe a mother transferring her emotional needs to a son when they don't have or those needs are not met by a husband, but it's just terminology, invented by psychiatrists to describe the situation. It does happen, I watched my grandmother do just that when my grandfather died, we all just said that she came from a generation when men ruled the roost, she didn't know how to mow lawns, do tax, set the time clock on her lights, so on and so forth. But she really did expect my Father to slip into my grandfathers role of protector/male in her life.
If you really can't tear yourself away from the other place, then you need to remind yourself that those ladies are also in pain, they are coming from a different perspective and it isn't the same as yours.