AIBU to think by age 40 I should have more say over how I spend my days?

You need to say no and let people get on with it. I’m in the same stage of life (though I don’t have parents anymore, I do have in-laws). But I have Dh and teen/primary age dc and a farm to run and I have cancer. I haven’t felt any of this pressure.

Dh entertains himself and if he wants a day out, he takes himself/dc on one. Dc are old enough to entertain themselves too. I do give lifts, but it’s just a quick 10/15 minute drive now and again, and Dh can do it too. We had no house guests this year because I say, nope, not catering for anyone. I’ve spent loads of time reading, gone on some lovely solo hikes, wild swims, watched a few films, been sat in front of the fire with a coffee for 2 hours now with no plans for the day other than a quick trip to the shop and the pharmacy. Dh is taking youngest dc away for the weekend so then I’ll have 4 days of doing whatever I want, with a bit of taxiing for eldest.

You get what you create. You have to start saying no to stuff you don’t want to do or don’t have capacity to do. People will sort themselves out if you aren’t rushing in with a solution all the time.

You sound exhausted.

Some of this is just family life, some of this might be a boundary issue. How good are you at saying “no”?

Why do you “need” to take your DD an her friend shopping? Did you offer? Can’t they take public transport? Why is your presence required at all?

Do your children know how to use public transport? If not, teach them. They will of course still sometimes need lifts, but you should encourage them to use bus or train where possible - it’s an important life skill.

Aging parents are difficult, but you can still set boundaries. Divide their requests into “wants” and “needs” and prioritise accordingly.

I’m not sure quite what your DH is asking of you, but he shouldn’t be assigning your free time without discussion. Explain you are exhausted and agree a new approach.

I know how you feel OP. I just went ballistic at my 42 year DS always expecting lifts and making me pick him up from his house 2 hours drive away.
Last year I had to drive him all over the countryside looking for a house to buy because he doesn't drive and I was waiting for a hip replacement at the time and in a lot of pain.
About 2 weeks ago I rang him up after the latest request and shouted, I'm not driving you bloody anywhere, get your driving license or stay at home.
There is no reason why he can't learn to drive.
He isn't speaking to me now 😂

I think you need to learn to be more stubborn. Put yourself first and say no. Stick to your plans. Even just occasionally!

Just say no. Tell DH that you don't want to go out today, tell DC that they will have to find alternative transport arrangements. Make a coffee, sit down with a book and put your feet up
Just be honest about what you are happy to do, and what you don't want to do, and stick to it.

Just say no?
Teens can make their own travel arrangements for a few days. If that's not possible, they'll have to stay in. Why can't your husband do the lifts?
Why are you doing what your husband wants, but not what you want? Why is he more important than you are?
Pur yourself first for a day.

If you work in education then you’ll know it’s perfectly possible to say no to teenagers and set some boundaries. Why haven’t you?

Just say no! Why are you doing stuff you don’t want to do? Your family needs to learn that you’re not there at their beck and call. Rather than stropping but doing it anyway, just say that you’re not up for that today and stay at home.

For me age 72. Good luck.

You really don't have to do these things. You are enabling people to put on you. You say no, not do what they ask you and sulk.
All this is in your hands.

Start changing things now. Say calmly that no one asked you how you wanted to spend the day and you have decided to have a peaceful day at home. Your husband can go out if he wants. Tell your teens no more lifts without asking and getting agreement the day before. If needs be book yourself a hotel overnight stay for some peace.