Well, maybe your friend just couldn't handle it. I've seen coaches to this too. Sometimes they would ask me, "Can I give you a feedback back?", and when I agreed, I got good value from them, usually their observations and perspective, which I valued.

However, when I do have something honest to share with them, and even if they said yes to "Can I give you a feedback?", they get very defensive. Well, I guess not every one is open to be shown a mirror, eh?