@Ragwort you misunderstand me. I don't mean winding down life, I mean winding down on the active parenting/responsibility. My Mum still works part time, volunteers, runs her allotment, travels, has a very busy social life and is doing up a house. MIL works full time, volunteers, supports FIL through marathon training, exercises, hikes, runs a couple of social clubs, hosts students at home. They're actually busier than ever but they can be because their children are fully independent.
What I meant is that they aren't actively running a non-driving teen around or topping up student loans, nor do they have DC living with them. They host Christmas as much as ever but they aren't taking responsibility for other people's Christmases iyswim, more hosting disparate families who come together as a wider unit. My friend has a 19yr old and 17yr old at home and had to drive them to parties, pick them up late on the 24th, take into account their presence in the house over Christmas. Her DC need her active support on a daily basis in a way that my parents/ILs don't.
I'm anticipating the next stage, the one where my dc are independent and for me, that will happen in my 50s. I plan to have a whale of a flipping time in my 60s, not give up on life!