DH was the family scapegoat for years, then by extension me and our kids.
SiL was the golden child, and by extension her current husband and her kids.
Then a few years ago, MiL had some kind of epiphany. Apologised to us for the way she’d treated us for years, apologised to DH for the way she’d treated him growing up and has been a changed woman ever since. No idea what caused it, but she has genuinely changed for the better. Comes and visits, calls us, rings/texts our kids, takes an interest in their lives - I mean, the bar is still quite low here, but it’s better than it used to be.
SiL is livid. She cannot stand it if MiL spends any time with us and will phone constantly or create some drama when MiL is visiting.
She hates that DD1 is at uni and DD2 is about to start. Is negative about any of my kids accomplishments or achievements. Hates that DH has a successful business. Hates that 25 years later we’re still married. Hates that neither of my kids have been in trouble with the police or do drugs, have friends, go out to the pub, etc, etc. Just normal day-to-day stuff really, she’s insanely jealous of.
We live a couple of hundred miles away from her so don’t see her or have to put up with her nonsense very often.