Sometimes, yes.
I'm not married and my life revolves around world travel. Sort of. I also hold a season ticket to a soccer team 2 hours away, so as a result of all that I lead very different lifestyle from most people who live here. While most of my coworkers discuss kids and what they're cooking for dinner, or whatever, I often find I can't relate to their discussions at all. I also have a hard time finding people I can relate to. Even people who aren't married often have wildly different interests than me, it's not easy to find people who love travel and soccer as much as I do. Throw in the fact that I'm an extreme introvert (in many ways), and yeah, I often do feel alone.
It's one reason I love travel. I meet so many people when I travel who I can relate to, whether they're 22 or 52. After each trip I usually go through a phase where I just can't relate to anyone here, and spend a lot of time daydreaming about my last travel destination and the people I met there..
Mind you a lot of this alienation is psychological I guess, since it's easy for me to meet up with some friends, and even though they lead slightly different lifestyles than me, we get along and have a lot of other things in common