Coming from someone who's started over several times in her life, I can relate to the feeling. Personally I think it's sometimes needed.

My dad used to tell me that if someone tells you something about yourself and you don't like what you hear, you're the only one who can change it. So change it.

It's an over-simplified way of looking at it, but that doesn't mean it isn't true. Sometimes actually MAKING the change is amazingly difficult and it's not so easy sometimes to completely remake yourself. But, it certainly can be done. And sometimes, it does need to be done. But, it really would depend on the context I suppose.