Real courage isn't limited to the battlefield. It can be as simple as remaining faithful when nobody's looking.
We've all done the wrong thing because no one is there to notice — well, God does. Act as if God were on your shoulder with you for every decision. Rely on yourself (and count on God) to have the courage to always do the right thing!
Have I not commanded you? Be strong and courageous. Do not be terrified; do not be discouraged, for the LORD your God will be with you wherever you go.