I hate to say this, but I spend several hours daily on my side project too. My wife hated me for a while, now she seems to accept it. I can best describe it as an obsession. You have something u need to do, u cant rest or enjoy something else until it is done. When I shower I think of my project and when I take a walk, I think of my project too. Complete obsession to solve the problems; one problem after another problem.