When we were first dating I visited DH (then bf) at his parents house and when it got time to take me home bf car wouldn't start. Was a 20 minute drive back to mine, no direct buses and it was late evening/dark. BF asked his dad if he could borrow his car (he said yes). His mum pipes up "the car is half mine and I say no".
Also during those early dating years DH took me to an expensive hotel for my birthday. His dad said "that's the most expensive shag you'll ever have" in front of me.
MIL wore a white dress to our wedding.
When we had issues conceiving she would bring me lots of articles about female infertility, even though she knew we'd found out DH had a very low sperm count.
First pregnancy ended in a MMC. The day after I'd had an op to have it removed, DH had to collect MIL and bring her over our way as she was having a make up trial before her DDs wedding. She walked in and saw all the cards and flowers (she'd arrived empty handed). On her return she thrust some flowers at me that had obviously been bought at the local garage.
Two weeks later she expected me to drive 20mins to pick her up, then drive a further 45 mins to take her to her DDs hen night, drink nothing and do the return trip in the early hours. Fortunately I could use my recent miscarriage and not feeling up to it to decline. She was furious.
Took our two DDs out for the day to a local stream with FIL on a hot day and didn't keep the youngest (2yo) topped up with sun screen. Toddler was pale skinned and came back with bright red sunburn on her back 😡
There were loads more. She hated that I'd taken her precious boy away from her.