Sorry if i come off as blunt, but i think we need to focus on the practical aspects on solving this.
Alright, you figured the problem you need to solve.
If you are insecure about your art, practice to get better. You have improved a lot over the years, and i gain nothing by complimenting you. You are not my boss
If you are insecure about your writing, practice your storytelling. How do you practice that?, the answer is surprisingly simple, but not easy. Is the same as art. Learn the rules like a pro to break them like an artist.
If you are insecure about you as a person work on yourself. Do something that is good for you and you enjoy, be it a hobby, excercising, learning something new, self care or whatever as long as it's good for you in a way.
The solution to self doubt is an answer. You wanna know if your art will be good?, make some art. You wanna know if your story will be good?, make a story, you wanna know if this project will succeed?, make it a reality!.
Don't make me yell "JUST DO IT"......but you get my point.
If i didn't think you could do it i wouldn't have spent my time writing this reply.