Attachment implies wanting a person to stay the same--especially in relation to us. There's a goal: Don't change. Since everyone and everything is always changing--impermanence is a univeral truth--relationships that deny this truth are bound to end in difficulty. Commitment, unlike attachment, doesn't say, 'You must stay a certain way for me to love you.' It says, 'We are in relationship, and I will be there with you through those changes.'
-Joseph Goldstein