A lot of people go through this, even professionals. My peers are often freelance illustrators making a living off their art and there are a fair amount of them that talk themselves out of doing the projects they want to because they're scared of lack of reception or that it will be a waste of time. It's a struggle that transcends skill level.
Maybe what you need to do is make the comic for yourself. You don't have to upload it, no one else has to see it. Only share it if you're comfortable with that after it's 100% finished. This might allow you to enjoy it while separating the need for external validation and give you the confidence to make comics regardless of it.
Will no one read this? Doesn't matter, you're not uploading it. Is the concept stupid? Maybe, but you like it and you're going to do it anyway.
As for my own frustration, I'm just... tired of finances holding me back. So tired. I've been doing my comic alongside of a full time job for 5 years, and only in the past year have I been able to make a slow transition to the flexibility of freelance so I have more time to dedicate to the comic. I'm so sick of having to split my focus and having the workload of basically 2 full time jobs at any given time. I feel like if I could just get enough support for a year or two to really produce a lot of pages and focus on making my business sustainable, I could make actual strides in making a living doing what I love. It usually comes down to that catch 22 of: Need to devote time to the business to make it work, can't devote time without money to pay the bills, need to make money with a normal job, job takes up tons of time and energy and now I'm unable to devote much of anything to the business. It's a dumb cycle I'm trying REALLY HARD to break.