J.R.
Mine have definitely changed - more based on geography than age/maritalstatus/kids.....my very best friend since grade school lives over 2 hours away, but, we are still best friends, and I know either of us would be there for the other without a question, in a heartbeat, in time of need, but really we only get to spend a significant amount of time together a couple times a year. Like this last week, when we invited her to join us for the weekendat my grandparent's cabin on a lake in WI. When we do manage to get together, we stay up all night talking. We e-mail and IM, and occassionally talk on the phone, but when we get together, it is just like old times. I have a few other friends form Grade/High School that we still get together a few times a year too, and have a card playing party and eat pizza and talk about life.
I had some college friends that were in my wedding, but live 2-3 hours away, and then they drifted away after that, the bond was not strong enough to make the effort after a few years out of school. I tried but it didin't work, I did grieve the loss of those friends, but the season for them was over, and I couldn't be the only one making the effort. If we had lived in the same area, maybe less than 30 minutes or up to 1 hour apart, we might've found it easier to stay active friends, I am friends with them on Facebook, still, and I wish we had an in person connection, as we have history and have kids similar ages, but OH Well.
I have also (not in place of, but in addition to the old friends) found a few new mom-friends in my area, now that my kids are entering preschool and kindergarten, too. We get together some, but it is more about the kids friendships so far, though we get along well too, we are not "super close" yet. I have also made some older mom friends, at Church or through Bible Study or community organizations, some have kids in Jr High or High School and have been there done that and are great examples/resources, and others are even Grandmothers who are handy to have around when my own mom lives over an hour away.
Alot of my friendships where I can vent/talk/relate to other grown ups are online, people on one particular message board that i have belonged to since trying to concieve my first child, and we have had meet ups and play dates a few times with some of the nearby women and their kids a few times too.
Good Luck - making new real friends is kind of like dating, and it is a process!
Jessie