Is your husband an only child? Does sound like your MIL is relying on you guys for all her social activities?
As others say nip it in bud now. You be the one to make plans. I feel it is more important for you and hubby to have “Date days/nights”. Ask her to babysit while you do. You can have coffee/cake/wine with her before you go/when you come back and chat about your day?
You can plan when you see your in-laws without making them feel unloved. They need to respect the fact that your life is not theirs.
It may be difficult to become assertive if you are not naturally assertive but it is well worth it. If you let things lie you will just become disgruntled and resentful. Take the first steps today. Say something like
“hi I know we’ve arranged next Wednesday. We are busy that day can you make Friday instead? Oh you can’t, never mind how about next Tuesday?”
See what am getting at?
One thing though - her son HAS to be in total agreement with you. If he isn’t then you will continue to have problems.
Good luck you sound like a loving family and am sure you will get round this.
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