To feel sorry for SIL re empty nest, but to think she brought it on herself?

[Summerbreezing]

Mu SIL's youngest child is leaving for University in September. So it will be just her and BIL for the first time in 25 years. I can understand this is a big life change for her and the empty nest can be hard to come to grips with.
However, SIL is incredibly down about it and acting as if her life is practically over and will no longer have any meaning. I feel very sorry for her but I also think she really never thought ahead to this time while her children were growing and becoming gradually more independent.
She gradually dropped all of her college and work friends as soon as she had children and just replaced them with 'mummy friends' from school and toddler groups, most of whom drifted away as soon as the children got older and no longer wanted to play together. She ignored all suggestions from her husband that she go back to work part time or do some kind of a course to get her out of the house. I asked her a few times if she'd like to come along to an evening class with me or join a gym but she wasn't interested. She basically just invested all of her time and energy in her children, to the exclusion of everything else, and is now totally bereft.
AIBU to think this is a very short sighted thing to do and it's important to remember that your children won't be at home with you forever and you need to retain or rediscover some interests and activities of your own for when that day comes? I hate seeing SIL like this, it's almost as if someone belonging to her has died.

So she's had time, her DCs haven't needed her to do anything, she hasn't actually filled her time with her DCs (as you said she's been sitting around the house 'doing nothing'), so her life won't change all that much.

She doesn't seem to want friends. She hasn't kept in touch with people, and that suggests they were more acquantences, not actual friends. People to chat to, people she shared that bit of her life with, not people she actually cared about. Harsh, but if she isn't very good at making friends or interested in having friends, then just providing opportunities to meet new people won't change that, she'll just have new people to chat to for a bit, doesn't mean she'd move them to being 'friends'.

It sounds like you are a 'busy' person, she is not. I know a lot of busy people find 'time wasting' impossible to understand, and assume people must only be time wasting because they can't think of anything to do. Sadly, while you can make people do stuff, you can't make them want to do it. She doesn't want to do stuff, until she does, nothing you or your BIL can say will change that.

(Oh, and I'm a 'busy' person as well, I like having stuff to do, I hate having no plans for a day, but I have learned that a lot of people aren't like me.)

I think Mary put it beautifully.

I fail to see what 'salutary lesson' she needs to learn. She had a vocation she gave passionately to for 25 years - of course she is a little lost now that it is moving on. A part of her life has died - in the same way I imagine a person who retires or whom is made redundant after 25 years feels a part of their life has died. She is allowed to grieve for the passing of this stage. She obviously enjoyed it - loved it, so why should she be looking forward to it ending? That doesn't mean she won't, in her own time, come to terms with its passing and move on to an equally rich and happy stage in her life - that might or might not involve night classes.

In 3 years if she is depressed and still mourning you are entitled to be concerned. At this time, with her youngest not even out the door yet, it seems both presumptuous and pejoratively judgemental.

It's possible that your SIL is the MNer who put toothpaste on her DC's toothbrushes in which case she is probably enjoying a lovely long lie-in now.

YANBU to be concerned but you've tried, she's made her own bed and will need to decide for herself how she wants to spend the next 20-40 years of her life. I'd stay out of it.

Mary, not everyone who isn't a 'busy' person enjoys and aims to be that way. I think quite a few people have a mild depressive or even self-destructive streak, or just a lack of confidence, which holds them back (not implying this applies to OP's SIL).

People are very mysterious, complicated and secretive. It is impossible to get inside someone else's mind.

Can I quote Thoreau?

"Most men lead lives of quiet desperation and go to the grave with the song still in them.”

SIL sounds like she's still living through her children - constantly ringing and texting a grown up daughter who's away at university is not healthy for her or her daughter. Of course any normal mother is going to be very absorbed in her children and their lives, particularly when they're at the young and dependent stage. But as they get older you need to start letting go a bit. Otherwise you're not only storing up problems for yourself, but also making life difficult for their children. They cannot live your life for you, or be constantly at the other end of the phone, and it is unfair to put that kind of pressure on your children.
In my view a really good mother is one who brings a bit of balance into motherhood and lets her children see that she has some kind of a life away from them. It doesn't have to be a very busy one, but the last thing any older child wants to see is a mother just hanging around the house waiting for them to come home in the evening.

IMO, what Mary wrote is thought provoking and spot on.

As a long term single Mum to an only child, this summer has given me a glimpse of what life will be like when dd leaves for university in a few years. When she goes, I will well and truly be on my own. It has been a huge wakeup call. While that freedom may ultimately be exciting and liberating, my life will be more empty in the short term. The future is a great big blank unknown, and that is sobering.

I know I need to revive interests, find new hobbies, get out there more, etc. The problem is that, atm she still needs me around very much for practical reasons (as well as emotional support), so I'm not in a position to do very much....but starting to think is the first big step.

I know I will figure it out with time. And so much of this sort of thing seems to gradually evolve anyway - it is often not simply 'making a plan'. It takes time to adjust to the new reality of a major life change - whether it is moving to a new area, becoming a parent for the first time (or adding to your family), starting a new job/profession, death of a family member, etc. Some people sail through hardly missing a step, while others struggle as they find their way.

Yes OP, perhaps your SIL should have/could have done more to prepare herself. I would urge you to continue to support her and show compassion. It is undoubtedly her adjustment to make, and hopefully she will eventually find her way.

I worked with a lady like this, her DH and DS's were her entire life. Her DH died very suddenly at the age of 58 and both her DS's got married and went to live in another part of the country, necessitating an overnight stay if she was to visit. She ended up becoming an alcoholic over it. She's a lovely, lovely woman and I felt so sorry for her but she had over invested in their lives and hadn't made any time for herself. I couldn't bring myself to judge her though. So sad.