I just read your post. I know, you wrote it 6 months ago, but that's how behind I was on some of my Mamapedia emails. Anyway, maybe hobbies are still something you're thinking about. Did you find one or two for yourself?
Call it a hobby and it's just another obligation in my book. I call it "doing what I like to do". And when it's not fun anymore, I stop doing it. Below are a few things I like to do.
--BOOK GROUP is a must in my life. I've been doing this for 8-9 years now. It keeps me reading and talking with friends at least once a month. It helps me to get outside of my life. And each December we go out to dinner someplace. Sometimes we even talk about the books! Go figure!
--GARDENING gets me outside and makes our yard look nicer and/or feeds our family. If your kids are up for it, it can be a fun activity for them as well, especially when they're little. But I mainly do it for my own pleasure. (I haven't succeeded in getting our 15 y.o. son to participate lately. At least he likes the results in the end. : P)
--WALKING (not as often as I'd like...gotta up the ante on this one!) gets me outside and works those muscles that gardening doesn't.
--"WE" GROUP (WE = Women Empowered in Work and Life = http://rivercenter.us/node/589) is a new feature in my life at a local parenting/community outreach center (2X/mo, I make it when I can). It's for women 40 and over who are in transitions...kids getting older, wanting to make a change, looking for work (not your issue : P), newly divorced, or simply sorting out life in a constructive way.
--FAMILY TIME--Periodically, we love to have a BOARD GAME NIGHT, or a MOVIE NIGHT, RUN-AROUND-OUTSIDE-with-the-soccerball/baseball/softball/basketball/etc. or CHILL-IN-THE-LIVING-ROOM NIGHT. The chill-in-the-living-room night takes many different forms. Sometimes we pull out books and all read our own books, sometimes we read out loud a book our son is reading (yes, he still loves doing this at 15 : ), sometimes we light a fire in the fireplace and just visit, sometimes we torture our son with some of our old vinyl records (he used to love this memory-lane thing, but bolted from the room a couple nights ago when we tried that again, LOL). Or since we built our new 14x16 sunroom addition, we also have CHILL-IN-THE-SUNROOM TIMES. Sitting there during meals or other times, we enjoy watching the hummingbirds (or other birds earlier before the bears warranted taking down those feeders), chipmunks and other wildlife in our yard, storms lighting up the sky, listening to our son playing guitar, torturing each other with bad puns (my husband is uncommonly gifted in this area...groan!).
When our son was young, we used to have FABULOUS FRIDAY DANCE PARTIES or STUPENDOUS SATURDAY (or Sunday)...MANIC MONDAY...TERRIFIC TUESDAY...WEIRD WEDNESDAY...you get the picture. I LOVE to dance and that was the only way I got to do it when our son was younger. It was a ball and the three of us would just dance our hearts out. Once he became self-consious, that went away, *sigh*, but they were a riot when he was little and it let off a lot of steam.
MEMORY BUILDING is also a lot of fun as a family. When our son was 7 or 8, we started doing 1- to 2-week vacations almost every summer. As we pulled out of our driveway each time, we'd yell, "ROAD TRIP!" and be on our way...
1) Train trip from the east coast to Chicago to Denver to San Francisco, to Glacier National Park, and back. Stopping at various places to spend a few days and to build those memories.
2) Drive from east coast to Wyoming and back. We read an entire Harry Potter book out loud on that one.
3) Family reunion, followed by train trip from the midwest to the Grand Canyon and back.
4) Drive through Canada from east coast to the Boundary Waters in northern MN and back.
5) Every 3-4 years, my siblings (we had 6 kids in my family, one has since died) mastermind a family reunion in some place we want to explore--Oregon Coast, Bass Harbor (ME), Boundary Waters (MN). Or we'll get together with a bunch of cousins on one side of the family or the other. I think we've maxed that out for a while, but we're thoroughly enjoyed them while they lasted.
In the past, I've done a ton of VOLUNTEERING--for my church, for local organizations, at school. Just be aware that volunteering can be full-time job if you're not careful. Boundaries are important when you do volunteering to make it a positive experience for all involved.
WATERCOLOR CLASSES and PARENTING CLASSES helped express various parts of me through the years as well.
So, my list includes more than just "hobbies". But they are all things that I thoroughly enjoy/ed. They helped me maintain perspective on life and family and many of them still do.
You sound like your life is incredibly full with work and taxiing your kids. Whatever gives you a little space to smile deep inside is what I would aim for. Whether it's with your family or not. That's what I'd aim for.
I hope you found something that works for you. If not, maybe this list might strike a chord in you. Best of luck!