I have a friend who is vastly different from me. We don't see eye to eye on many subjects. It is the most fulfilling friendship I've ever had. He is in every possible way a "true friend." Despite our differences our friendship only grows stronger. I think the fundamental issue is that neither of us ever really want to change the other. We care about the others happiness and often our discussions are to help one another see things more clearly and from a different viewpoint.
Anyway, I guess the point of this musing post is just for you to think a little deeper about the friends you have. Be grateful for them. Do what you can to reciprocate the influence they have on your life. And realize that just as they probably don't realize the full effects they have on you, so also you never know what your caring example means to them.