I don't have a mother in law - but when I did- I loved her. She was wild, her name was Margaret and she called herself a prayer warrior- and the first time I ever went to meet her she told me to stand up and pull my skirt tight across my hips so she could see my figure - she said, 'You're a nice size...slightly hippy - but that's good - you'll be able to deliver babies...
Then she showed me her scar from her mastectomy - even though I told her I really didn't want to see it - that I was squeamish - she said, 'Don't be a baby - I had the operation, and you can't even LOOK?!' ...then she made me sleep out on the couch outside her bedroom and she kept the door open all night and I woke up in the pitch dark and she was talking to someone - I couldn't figure out who- and then I heard her put the phone down and pick it back up and realized she was calling people and praying with them at 4:30 in the morning.
She liked me - actually tried to talk me out of marrying her son- she didn't think he was good enough for me.
She was a trip - actually one of my favorite people ever.
So different than my mom (who's also a favorite of mine) - that's probably why my husband loved my mother more than his own...I think he found my mother a little more conventional and to his taste as far as what he thought a mother should be.