That's a deeply rough experience and it underscores how difficult it is to be an indie game dev. Years of work only for the project to basically go nowhere as a result of some bugs you had not caught. I'm sorry.
I will try to place emphasis on fixes myself but there is no way a solo developer with no playtesting team will identify every possible issue so this is definitely of concern to me going forward on my own projects.
My recent Escape Simulator level for example was free and graphically tons of custom stuff went into it but it got trashed likewise due to a number of serious bugs and most of them I hadn't even realized existed until release so... that is a good example from my end but at least that was a project scaled in a month not years. It tells me this is a huge project ruining risk and I need to finish not only the core features of upcoming bigger projects but playtest heavily with anyone I can find. Sit back and see where people are getting stuck. Take notes. Adjust and fix as needed.
Hopefully that goes well.
And hopefully you can recover from your first launch as a lot of what you did the first time came close to succeeding.