Just ask Hugh Howey, James Lee Burke, Lisa Genova, Elmore Leonard, Kathryn Stockett, Heidi Durrow and more. In other words, if you believe in your work, don’t give up!
“Unfortunately, authors can be susceptible to taking feedback from agents/editors as gospel or the final word on the market potential for their work. That is a mistake. Their feedback can be useful, of course, to the extent it demonstrates where you might have failed to make your business case, or it might reveal something you didn’t know about the market.” Jane Freidman