I'm sort of the same way, though it does have its costs in terms of friendships and other things related to stability.

I think the root value here, however, is that of intentionally pushing yourself outside your comfort zone. This can be done every 5 years, or every day, or somewhere in between. It's something I swear by because it keeps my mind fresh and stimulated. Taking a class unrelated to anything I've ever done is a nice example of something that can be done every few months or so.

Or, since Wear Sunscreen was mentioned here....Do something every day that scares you.