I've posted about my MIL before under an old name, and this is a bit of a WWYD / AIBU.
For context, DH is 29 and has lived independently since the age of 18 (university) after which he never went home (to a small quiet town) and instead moved to a big city with his job, which is about 2.5 hours away from mil and where we both live. We / he visits mil every few weeks and she comes to us every few months.
Mil has 7 children (!) of which DH is the eldest. The others (nearly all adults, some teens) all live with her (no fil in the picture). She has always had trouble dealing with DH being independent and not being her baby anymore. It's obvious that her identity is all about motherhood and unfortunately she doesn't do anything for herself, have any hobbies, or socialising at all, apart from look after them, cook, clean etc and seems to live through their lives. I think this is really sad but I am looking in from the sidelines and there's not much I can say. DH thinks the same about the situation and does try to encourage her to do other things but nothing changes.
Recently DH was sorting through some life admin and looking at a subscription / membership for a magazine which he first set up years ago when he was about 17 (geeky hobby related). He decided he was no longer interested in it and wanted to cancel the quarterly subscription but when he phoned up it turned out the subscription was in his Mum's name (mil). She must have set it up for him when he was younger because he was under 18. The magazine company refused to speak to him as he was not the named account holder, and so later that day I rang up and pretended to be his Mum to cancel the subscription. All they asked was if I would 'authorise' them to speak to DH, and then DH took the phone and took about 2 minutes to cancel it, no big deal.
DH spoke to mil on the phone last night, to catch up and arrange details for a forthcoming family wedding. He mentioned in passing he had cancelled the subscription, and mil was really sad and upset about it! First of all she said 'why on earth didn't you ask me to phone and cancel instead of petal', the answer to which was that I live in the same house as DH and it made sense! (I don't think mil was worried about the legality of it or anything as it was only a trivial matter and wasn't like we were on the phone to HMRC posing as her or something. It was more about the fact that he didn't come to her for help.) She then went on to say "it's so sad, I've been looking after that subscription for you for over ten years," and he said she was on the verge of tears! AIBU to think WTF?!!?
Next she asked if she could add him on Facebook and Instagram. DH said he doesn't really use them much (which is true). She also asked if she could see his LinkedIn - FFS! - and DH said he would rather not add his Mum as a contact as it's for his work and his his acquaintances are all professional! Anyway, after the phone call she still sent friendship / add requests! DH's sibling tells him mil set up brand new accounts especially to add DH and said she wanted to see his photos.
DH started a new job in January and mil began asking him about his salary. He said something vague like 'it's a nice step up' and she asked for the figure. This is an interesting one as I don't know how people feel about sharing salary details with their parents (?), and I'm sure it depends on how close you are, but in the context of her behaviour it just got my goat a bit and I thought she was out of order to ask for full details!
Finally DH's brother (27) is hoping to move out and has been looking at flats in a town near mil. Mil was upset about this and saying it was 'ridiculous' as how would sibling manage all his laundry and cooking...!
This is in the context of a history of this type of stuff. As you can tell I am ranting and letting off steam!