As a creator, you have a responsibility that is both simple and awesome at the same time.
You have to see the project through.
There are a number of steps that you have to follow in order to see the project through to completion. And for our purposes here, I'm only going to talk about finishing the first issue. The first issue is all-important, because subsequent issues are just repeats of the steps for the first.
The idea is simple: you want to create a comic, and you've done all this work in order to bring your idea into the world--you've saved money, you've researched what it takes to make a comic, found reliable creators, and gotten the work done. You're now holding a comic in your hands (that you printed at home yourself).
Now, you have to finish the job. This means you have to do what you can to bring the comic to market.
As an editor, I have a lot of "finished" scripts in my files. These are scripts from clients that have been edited, but haven't gone anywhere since. I've also been sent comics that have been "finished" in terms of art and lettering, but the creators haven't done their part to try to bring their work to market.
They haven't followed through on their project.
I understand that submitting isn't fun. It's nerve wracking, and the overwhelming bulk of new creators don't handle it well, especially when the project is rejected. Rejection is par for the course, though.
There are ways to bring your book to market that is outside of the mainstream submission process. The game changer is Comixology Submit. There's no real curation there. As long as you abide by their guidelines, just about anything can get through.
There are also webcomics. You can put your book online and let people read it for free. (Freemium isn't a sustainable model, just so you know.)
There are more options out there. The bottom line is that you have to see it through to the end. The end means getting the comic you made out to readers.