But I realized today that confidence is tricky. Because there is a line where confidence stops being attractive and instead becomes repugnant. I've been thinking about it all night, and I've realized what the difference is.
It's humility. Confident people accept their imperfections. We all make mistakes, but a confident person moves forward, neither dwelling on them, nor denying them. Overconfident people lack that humility. In all of their interactions, they would have you believe they are perfect. Not only do they do everything better than everyone else, but they also are incapable of making mistakes.
Overconfidence is simply repulsive to me. It is either a willing lie or a complete delusion. In either case, if they clearly show no signs of humility, I don't want to associate with them.
Remember this in all aspects of life, including your writing. Never be afraid or ashamed of your love for writing. Be proud of this endeavor and strive to reach the level that will make you happiest. As you improve, be proud of the accomplishments you have made. But, always be aware of your flaws, too. Don't ignore or deny mistakes you've made. Overconfidence will keep you at the level of mediocre writer for as long as you believe the delusion that you are without flaw and beyond improvement.