OP here. There are so many posts here I'd like to respond to because so many of you have hit the nail on the head.
I really don't mind driving my daughter around. When I was a kid we lived way out in the country, and my parents tried their best but were not always willing or able to drive me into town for stuff, and I hated to ask. Also, they were good about coming to as many of my school-related events as they could, but they didn't have time to volunteer in my school, chaperone field trips, etc. It really wasn't much of a big deal, but I always told myself that when I had kids I would make sure I was available to them for all of these things. Many years later, DH and I have made sure that I have a flexible enough situation to be able to do these things.
What I resent is that my daughter and her friends seem to be assuming that I'm always available to them--all of them--probably because I always say yes. I resent the last minute "requests," where DD texts me when I'm on my way to pick her up and asks if I can also give friend/friends a ride and I know they're probably standing right there with her, and I would seem like an ogre for saying no because there's no reason I can't except for the fact that they have never once given my daughter a ride, and only one of them ever even says thank you. They are nice, good kids and not rude at all, and they do say goodbye and I'm sure they just don't think to say thank you, but still. I made sure to tell DD to be sure to thank any of her friends' parents who ever drive her anywhere, but that rarely happens, haha! Luckily, I really do like all of her friends and don't think any of them are bad influences on her or anything like that. So that's good, at least!
What I'm worried about is that I'm sure once my DD starts driving they'll be wanting her to drive them around. We plan on having a car available to her as soon as she gets her license so she'll be able to drive herself and my son around, run errands, etc. Really looking forward to that! But I think we'll need to lay some ground rules about her not becoming the chauffeur for all her friends.
I think I just need to have a talk with my daughter and let her know that while I am always glad to get her where she needs to be, and that I'm glad she's active and busy and not sitting home playing video games all the time, it IS something of an effort on my part and I'd rather not do any more of the driving than strictly necessary. So when she and her friends are making plans, she needs to do her best to have her friends ask their parents to do their share of the driving rather than just automatically volunteer my services. And she needs to ask me ahead of time, rather than let me know as we're getting ready to go who else we will be stopping to pick up on the way.
And I'm really looking forward to the day she gets her driver's license! Although I know, I know, I need to enjoy these times while I can. Why is it so easy to look back wistfully on phases of our children's lives that have passed, but so difficult sometimes to enjoy the moment?