Just ride when you feel like riding. Try to enjoy it. Little by little it will become your preferred choice and the exceptions will become rare. Maybe it will even help with your insomnia.
I think that which ever commuting method one relies upon, one always has some kind of a back-up plan because nothing is bullet-proof (except kevlar). The bus-drivers go on a strike, your car doesn't start, the bike was stolen or you stepped on a land-mine