Maybe this isn't helpful advice, but don't take product failures so personally. They are experiments and learning exercises, and most companies fail by default. Of course it depends greatly on your life situation, i.e. do you have a job that can support you while working on stuff as a side-project? Or are you attempting to launch something as your full-time day job with limited savings or income? (10x more stressful)…
I would argue that it is possible, even necessary to try monetize early (but only after users acutually use the product). Maybe charge some small amount. PG may have written about it, I am not sure which essay.