Writing.Com General Discussion

I'm brand new to this site and have very little experience with online interactions through forums. Having worked in a library, I've often been asked to read others' writing, which always makes me cringe. I'm sensitive to criticism on my own writing so I don't know how to give an honest review. I'm normally overly generous. That said, I assume others will do the same thing when asked to read what I've written. How can I get practice and honest feedback without getting discouraged?