What are some of the things you tend to think about?
Are they usually positive thoughts or negative thoughts?
Is it the truth or are they lies?
Rather than thinking only of what you've lost, think about how God may be using your loss to benefit you. Rather than thinking about how miserable you are, ponder how you can make someone else happy. Rather than worrying about what will happen tomorrow, figure out how you can be a blessing to someone today. Instead of grumbling and complaining, PRAISE God for all the things He has done for you!
SO often what we choose to think about is what directs our attitude... our mood... or how we respond to something.
"The way we think determines the way we feel and the way we feel influences the way we act!"
"And now, dear brothers and sisters, whatever is true, whatever is noble, whatever is right, whatever is pure, whatever is lovely, whatever is admirable—if anything is excellent or worthy of praise— dwell on these things!" (Philippians 4:8)