A WN author once told me that she began writing because she didn't want to forget about the ones she imagined. She wanted to go back, reread and relive the moments in it. Then, she started posting it because she thought maybe there would be others like her who would want to read it.
The journey in writing never ends. One day, you'll realize you're actually your biggest critic. You'd look back at your works and cringe. You'd scrap them and start anew. Sometimes others offer their opinions. They can be good. They can be encouraging. They can also be blunt. They can also be hurtful. I wouldn't say to ignore them but recall why your story is written the way it is. See if what they have said could be incorporated into making it better.
If not, well, like you, everyone has their tastes.
The biggest obstacle you'd face first is yourself. One of the reasons such negativity would affect a lot is because a person already had these doubts swirling in their minds. Those negativity just triggered what is already there. It's not going to be easy to overcome. Sometimes you'd want to quit. Sometimes you'd tell yourself you are satisfied with just imagining these stories. No need to write them. Well, I take you back to the first paragraph. You are your biggest obstacle but as long as your first reason to write is for yourself, you'll be able to rise above it all.
Even when you do, you'll find there's always room to improve. But also remember what you have brought out so far and overcame. You've made it this far, you can also keep going.