How Do You Deal With the Guilt of Shutting Someone Down?

Sometimes we have a friend who opens up too much, and we hae to remember what the role of the relationship is. You can always apologize for something later if yo don't think you handled it well. How do you deal with the guilt of shutting some one down? If someone comes to you and says, hay, i'm sorry, you know, if i screwed something up. Hopefully they'll receive that is like, this person values this relationship,. And they're thoughtful about it, and they'll hopefully try to maintain it.