If your MIL is rooting around in your bedroom on the quiet, the hilarious solution is always to leave lots of lube, dildos and kinky knickers strewn around the next time she is due. Teehee!
Yes to spa days being a cure for all woes, for it is a truth universally acknowledged that all ladies love to sit around in humid environments listening to whale song music, wearing fluffy gowns and too big slippers with cucumber slices on our eyes. Bonus points for consuming Prosecco at some point during this treat.
Your mother broke into your house, skinned your cat and left it simmering in a pan on top of the stove, and spray painted "Die cunts! Die!" on the kitchen wall? - Well User21594 would like to point out that her mother died 8 months ago and she would give anything to have just a few more hours with her, so you should count your blessings.
Similarly, if you complain when your MIL puts your DD1´s name down for a school down her street but 40 minutes from your house without telling you, insists on being known as Mama and demands you express so her "grandbaby" can have sleepovers with her from being newborn, then you are ungrateful because User21494´s in-laws have never shown any interest in her DC and she would happily swap with you.