You must, as a writer (and as a person, too, but that's another post for another day) accept your failings. Fact is, much of what you and I write is utter crap. I'm a proponent of the Million Word Theory. This theory states that it takes a million words to even begin to touch what you mean to say with any consistent marketable competence.
This just means writing takes practice, like everything else. And that practice--writing words you love as well as writing stuff you hate--gives you the ammunition to distance yourself from your writing. You are not the sum total of your ability to express yourself through fiction. The sooner you learn that, the sooner you'll open yourself to improvement, to submission, to rejection, and to forging ever onward into publication.
Because, whether it sucks or it's brilliant, whether inspiration carried you on a day-long high or every word splashed on the page accompanied by tear of insecurity, at the end of the day, your story is a product. As a writer myself, I know how much blood stains the pages in my slush. But my primary job as an editor is to go shopping. (It's a really freakin' great job; just wish it paid better.) In fact, I'm an editor who's shopping for six stories out of three hundred. I buy .o2% of my slush. It's like going into Nordstrom and buying only one pair of shoes. (As if!) And the odds are probably better at my magazine than at many others.
This reality is much easier to take if your story has already been chewed up and spit out in critique.
But sometimes, someone (a fool editor or that jerk critiquer) keeps saying the same stupid thing over and over...they just don't get it. They don't get you. Keep it in perspective. First of all, as we learned in kindergarten, we all won't be best friends. It helps to think of critique as a professional endevour, even when your critter is reading your passage aloud with different voices for each character and a Vaderesque narrator. Secondly, remember it's just the opinion of one person. I know I said that yesterday, but today it's the other guy's opinion we're talkin' about.
And, hell, maybe you actually agree with what they're saying--or not, or whatever; but those crackers are stale. Same shit, different critique. It can go on for years.
Mine was pronouns. The group railed on me over pronouns. And so I work at it and finally, that particular nit drops off the map. And then we get a new member coming to group and she says, "You know, Sex, I love your stuff, but why do you use your characters' names so much?"
So think these situations through carefully. Is their thinking flawed? Do they have a stylistic difference? Maybe they have an inability to express what they mean.
Or maybe you're stubborn.
Whatever the issue, don't justify, explain, or defend. There's no need. YOU ARE THE MASTER OF YOUR DOMAIN. This is your story. You are the final decision maker. And before you ask, yes, we've asked for edits at the magazine for stories we wanted to buy and had writers decline. My point? You may be sitting all alone in your darkened study with just the glow of your laptop to keep you company, but this is your story and no one can make you change it.
How to decide, though, what's worthy?
Consider the source. Is this an editor who wants to buy your story? A top agent who wants revisons before signing you? Consider their advice carefully, of course. Not just because they have power to put real money on the table, but because it's their job to know industry trends and standards. When I was a kid, headhopping was all the rage. Now rigid adherence to close third and first apply. Professionals make it their business to know what will sell and judge your work accordingly. The crutch: try it even if you disagree. They know. They won't last in this business unless they do.
Gut instinct. You know where you're headed. If the critter wonders why Gandalf appears at the start and mentions some fool ring out of the blue, and you know it's cuz by chapter four all hell's gonna break loose with Ringwraithes, then sit tight with a Mona Lisa smile. Kill your darlings only to a point. If there is a line of dialogue or a passage that makes your writerly mojo sing, then don't kill it right off. Think about what that passage is telling you about your characters and your story. If your critters don't see the importance, then maybe you need to pump it up rather than cut it.
But then, when feeling particularly defensive about particular advice, put it aside and look at it again later. Damned if I don't often find they were right. (Bastards, every one!) And majority rules: if two of three critters want a change, consider it very carefully. Some of this trust comes from good rapport, though. I hate when the critiqued interrupts me (cuz I'all love the sound of my own voice, don't y'all?). BUT, I love when they ask me (when I'm finished talking): Here's what I'm trying to do; any ideas? So, to me, the opportunity to discuss where you're headed with a piece is invaluable.
Basically, though, it's not your turn to talk. Sit quietly, hands clenched (among other things) and listen. Listen listen listen. Ask questions only after the torture session is over and be sure to say thank you.
Finally, trust your critters. They want to help you. Take it for granted that they like you, that they want to revel in your success,and bask in the glow of your prose and themes and plots. Because, really, most writers love doing critiques. I don't submit to Critters, but I crit for them. It's been a year, maybe, since I submitted to Crapometer. But I read it and crit there, too. Most writers I know owe me critique time because, as I said, it's truly better to give than recieve critique.