It's hard to sleep when your heart is at war with your mind.
Turn to Matthew 11:28 - "Come to me, all you that are weary and are carrying heavy burdens, and I will give you rest."
The secret is that you have to be willing to let go of your burdens and give them to Jesus. Too many times we give them up and then we take them right back again. Just for today, really try to let go and let Jesus carry your burdens/worries. You can always take them back tomorrow if you must, but just maybe you will find life is better without them.