I have to rest in the Lord. Let him take over the mental things, the worry, the "what ifs", the stress that is leading to my mental exhaustion. I must rest in Him to rejuvenate. The flesh is weary, the flesh is hard, the flesh is unknown. Turning to a God that is all knowing and putting faith in Him will lead to finally feeling rested.
Even youths grow tired and weary, and young men stumble and fall; but those who hope in the Lord will renew their strength. They will soar on wings like eagles; they will run and not grow weary, they will walk and not be faint. - Isaiah 40:30-31
Create in me a pure heart, O God, and renew a steadfast spirit within me. Do not cast me from your presence or take your Holy Spirit from me. Restore to me the joy of your salvation and grant me a willing spirit, to sustain me. - Psalm 51:10-12
Take my yoke upon you and learn from me, for I am gentle and humble in heart, and you will find rest for your souls. - Matthew 11:29
I will refresh the weary and satisfy the faint. - Jeremiah 31:25
For whenever our heart condemns us, God is greater than our heart, and he knows everything. 1 John 3:20