There are a lot of different aspects to the initial post. I am explaining, not defending, in response to texstyle's post. I am not saying this is what I believe/how I think things should be.
1. Why do some people 40-60 give up?
For some people, like me, dressing well is not something they grew up with. It might not have been done, it might not have been valued, or they weren't taught how to do it. Adapting to a post childbearing body can be challenging. And if you are staying home with kids and not bringing in income, it can be hard to spend the money and the time. And if you don't go anywhere, why bother? Also, if it feels hopeless, why bother. And if you have a weight problem it can be daunting to find clothes that fit. So, while I made sure my clothes and I were clean, there really wasn't any style for many years. Depression can certainly be a factor.
2. Why be proud of it?
It can be an expression of values. Some people think it is shallow to spend time and money shopping. It can also be defiance-since I can't make the standard, fit in, look good, why try? And I'll make sure you know I don't care so you can't hurt my feelings.
3. Should you say something?
It is hard in situations where if you don't say anything it seems like you are agreeing. With the woman who seemed proud of rolling out of bed and going, the most I would have said would be similar to ClaraT's first sentence. Something like, oh, it may not seem fair, but I am treated better when I dress nicely. Or maybe just, oh, that's an interesting choice.
As far as a close friend, if I saw a change I might have a private conversation and say I noticed you don't look like yourself. I'm worried about you. How are you doing? But when you are in it, it is hard to realize that you have a problem.
4. For people who grew up without a certain standard of self care, validation of looks, knowledge, etc. it can be hard to understand how challenging, how much energy it can take, to look nice. And how hard it can be to spend the money.