Hello!
I just noticed today that the game, out of nowhere, has had a MASSIVE boost in sales. That said, I think it is the right choice to continue working on the game at least for now to please the new players who just bought the game. If it really ends up picking up even more in sales, it will stay alive much longer. But if it declines again (Like back to averaging 0 a month) then I will proably just let it go.
P.S- This post isn't saying I only work on the game to make money. I work on it for fun. It just made me extremely disappointed seeing absolutely nobody play or buy the game for such a long period of time.