How does one politely tell one's mother-in-law to F off?

A lot of us go through this, dw you aren’t alone! Is she calling you or your husband? From now on, stop answering the phone. You can send a text (several hours later or next day) saying “I’m busy right now, will call you back tomorrow”. Then make the lengths longer, instead of calling back to send a text saying “what was up the other day?” Other excuses “Phone was charging so missed you the other day” or message “missed you earlier and going to sleep now, what was up?” And always give none responsive answers “good to know, thanks!” “Ah cool, night night!” “We’ve actually already sorted how we’re doing the living room, maybe you should renovate yours, it’d look lovely in your house?” If she starts calling your husband, then you set ground rules - answering the phone during dinner is just bad manners. Same when you’re spending time together. Treat it as if you still had a landline - would you answer? If not (because you’re out and about) then don’t answer, this goes for both. If his mum asks “but that’s why it’s a mobile! Why are you so busy?” The answer is “it’s rude to be answering the phone when spending time with my wife mum - I’m at work all day remember? We have limited time together.” I found that my in laws felt entitled to my partners time, and even more so when we got together as if it was a competition (it’s not). They also didn’t seem to realise that just because *they* have a lot of time on their retired hands, it doesn’t mean everyone else does. This also went for our weekends - that’s limited time to have fun/decompress from work. Your husband can have a calm chat about that with his mum/dad. A way around that is to be non-committal, if they ask what’re you doing next Sunday you say “not sure, we may be going out for the day to see friends we haven’t seen in a while” as if you say “no plans yet” they interpret it as time *they* can book for you. You can make stuff up, it’s fine, and stay at home all day in your pjs if you want. Your in laws need to get some hobbies - they’re retired and have too much time on their hands and the lockdowns mean MIL was able to fill her hands with you guys. She doesn’t want to go back to normal - she likes to be “mum” again. But your husband can gently suggest she join some clubs and make some friends to fill her time, and come with the compromise that you put dates in the calendar now when you’ll go round and see them. Best to become unavailable sooner rather than later!