Accept That Friendships Change Over Time

Friendships tend to depend on being in the same stage of life, and once that shifts — you are widowed but your friend is married; she retires but you're still running a business — the relationship can change too. One recent study claimed people of every age replace half their friends every seven years.  The lesson: Rather than clinging to relationships you've outgrown, you'll get more out of your friendships if you look for new friends with whom you share more similarities.

Risk the Fight

The longer you're friends with someone and the closer you get, the more likely it is you'll hit the kind of road bumps that can trip up any relationship. Rather than pretending the problem doesn't exist or running away, you'll need to confront the issue if you want to get more out of what is otherwise a valuable friendship.

"Sometimes it's more difficult to have these emotional discussions than not to have them," says Irene S. Levine, a professor of psychiatry at the New York University School of Medicine and creator of The Friendship Blog.  "But if you bury hard feelings, they can seep out in toxic ways and damage the friendship."

Dr. Levine's advice for approaching a difficult discussion with a friend: Choose a relaxed time, and talk in person rather than on the phone or via e-mail. Be sensitive, don't blame or attack, but don't mask your feelings either. And know that any discussion may just be the first in an ongoing conversation, one that will ultimately lead you to a deeper, stronger friendship that can offer even more in terms of honesty and intimacy.