All the king's horses and all the king's men can't put the past together again. So let's remember: Don't try to saw sawdust. — Dale Carnegie. American writer and lecturer (1888–1955)
If you can't sleep, then get up and do something instead of lying there worrying. It's the worry that gets you, not the lack of sleep.
Are you bored with life? Then throw yourself into some work you believe in with all your heart, live for it, die for it, and you will find happiness that you had thought could never be yours.
Do the thing you fear to do and keep on doing it... that is the quickest and surest way ever yet discovered to conquer fear.