Mmm, I think it will always sting, no matter how much you prepare yourself and harden your heart to that sort of thing. Your writing is like your baby; no one wants to hear their kid is no good. But it needs to be said for the good of that piece of writing, and because of that, you can look forward to improving and creating something completely beyond your current level.
I'm the sort of person that doesn't give any sort of in depth critique unless I feel the story is worthy of being fixed, and I have a feeling that most helpful critics are like that. Be glad someone took the time to read your full story, and tear it apart to show you those places that are broken. As writers, we can be too close to our writing, and can't see the flaws all the time, so someone else has to do the nastiness for us and pull our fics apart. You're allowed to sniffle at the initial pain, but after, it's your decision to either ignore the help, or take the hard road and grow as a writer.
So... and this may sound asinine, but I don't want to hear the 'oh, it's perfect, don't change a thing' comments. I want the, 'nice, but you forgot ___, and ____ confused the hell out of me, and do you really want to approach it like that?' comments. It's boring to feel like you have nowhere else to go as a writer. Sure, you can enjoy that feeling of other's loving your work, but what's to keep you from improving if you feel like you've hit some imaginary peek? If you were content with your current level of writing, I imagine it wouldn't have hurt so much to have your work criticized.
Good luck with it, and don't be discouraged. ^^