people who can't take constructive criticism over fandom related stuff are not going to have a fun time with constructive criticism in the real world, especially when you get to adulthood.
So it's better to try and become more open-minded in your youth, because otherwise you risk turning into a stubborn person who refuses other's opinions/perspectives/desire to help with constructive critique/etc.
So instead of bitching out at someone who criticises you, even when they may not have sounded as nice as they could have been, try and think more about their point of view. You don't even have to agree, but don't just run away from it or whatever. With clear bashing comments, just hide them. You have no obligation to answer to them. But when someone is actually trying to give you a thoughtful opinion on something of yours, even when you don't agree, at least try to meet halfway with them. Perhaps you two would both end up elaborating more on your respective points of view and just like that, you've managed to enlight yourself and become more open-minded!
Learn to ignore haters, take into account the constructive criticism, see where you can apply certain fix-ups and well, there's always going to be the occasional 'thanks but no thanks' type response, but for fuck's sake, you are all at perfectly good ages to learn how to deal with the different types of criticism.
Also please note that with the people who take the time to provide constructive criticism, it can be disheartening if their efforts are wasted. Being helpful to someone is a wonderful thing, so please acknowledge those who wish to help you, and create a positivity around being supportive of one another, sorting through issues without bitching or complaining, and all the rest.
Just... just hot damn, it actually really pains me to see people who refuse to accept criticism of any kind. Criticism can make you a better person if you can handle yourself right when receiving it. All it takes is acknowledgement and elaboration:
"Hey, thanks for taking the time to comment on _____! Can you tell me why you think _________?"
"Ah, the reason I made ______ this way is because ________________"
"What do you think should be my focus points for improvement?"
"What are some good resources for improving on _____________?"
Seriously, there are so many ways you can handle critique and gain further understanding, so it's such a peeve when people say things like "I'm tired of editing!" "Nobody would care if I change this" "I get so much bashing, I don't care anymore!" - because those sort of things have been said to me across all my years of fandom and let me tell you, sometimes I want to give them a slap and say "ACTUALLY I CARE, I CARE ENOUGH THAT I WANT TO TAKE THE TIME OUT TO ACTUALLY TRY AND HELP YOU! IT IS WONDERFUL TO LEARN NEW THINGS, IT CAN MAKE YOU A BETTER PERSON"
just... for goodness sake, the real world of adulthood can be really cruel. Not wanting to improve yourself or your skills at something can lead to you missing out on career opportunities, and by missing out on those opportunities, you could find yourself in a low paying job and find yourself bitching over not having enough money or not having a good job, which means you can't afford a proper home or mode of transport - and guess what? That's your problem.
So I really hope people will read this and take note. Hell, feel free to spread the word about this, because so many people don't seem to understand why criticism can be a great thing, so long as you approach it well. It's not something that will come naturally to you immediately, but it can be learned.