From my experience even when we know that people for some reason don't have the best idea about us, and just that fact hurts by itself. Believe, many times hearing what that really have against you can be more painfull.

Just because people think you are not doing things right and you need to change, it doesn't really mean that you need to change or that is even your fault.
I had some people complaining about me and telling me what I did wrong, and I barried myself more and more, trying to do things right, because I couldn't...but if I tried to say it, they would said to me that I didn't even try.