“The Lord said to him, “Go back the way you came, and go to the Desert of Damascus. When you get there, anoint Hazael king over Aram. Also, anoint Jehu son of Nimshi king over Israel, and anoint Elisha son of Shaphat from Abel Meholah to succeed you as prophet. Jehu will put to death any who escape the sword of Hazael, and Elisha will put to death any who escape the sword of Jehu. Yet I reserve seven thousand in Israel—all whose knees have not bowed down to Baal and whose mouths have not kissed him.”” – 1 Kings 19:15-18 NIV

Notice the solution to self focus and depression and the lies he gets stuck in. God reminds him to, 1) Focus on God’s mission by doing his tasks such as anoint people, 2) Focus on others in stuff like having Elisha succeed him prophet, and finally, 3) God gives him truth which is that he isn’t alone. When we are stuck in our heads we need to do something similar. We need to place our focus on God’s plan, other people, and truth. These are some of the basic strategies of fighting inward thinking. I also am thinking of just the basic general command, Ephesians 6:14-16:

“Stand firm then, with the belt of truth buckled around your waist, with the breastplate of righteousness in place, and with your feet fitted with the readiness that comes from the gospel of peace. In addition to all this, take up the shield of faith, with which you can extinguish all the flaming arrows of the evil one.” – Ephesians 6:14-16 NIV