The best way to get rid of the negative thoughts is to crowd them out with something else bigger and more beautiful: worship of the One who holds everything in His powerful and capable hands.
Connect with positive people who will stand in faith with you and lift you up in prayer. Study the Word of God and put your faith in action, for the Bible declares, "Faith without deeds is dead" (James 2:26)
So much of how we think, feel, and live depends on our vision-what we choose to see in any given situation.