Paul reminds us that our outer self is wasting away, but our inner self is being renewed day by day, and this connects deeply with what you are experiencing right now. On the outside, everything seems like a sign of the end: fatigue, doubts, the impression that strength has run out and hope has faded. The feelings you carry are real and do not need to be denied or diminished.
But in Christ, what seems like the end is never the final point. Many times, it is a semicolon that God uses to continue writing your story. He is not the author of abandonment, but of continuity; He does not close chapters with despair, but with the promise that there is still something to be revealed, even when you cannot see the next paragraph.
The Bible does not call tribulations "light and momentary" because they are simple or painless, but because, in light of eternal glory, they do not carry the same weight. God does not minimize your pain, but puts it in perspective: the present suffering, no matter how intense it is, is not the final word about you or your future.
What is hurting today is true, but it is not definitive. In Jesus' eyes, nothing you live in faith is wasted: every tear, every weary prayer, every step taken even without strength is embraced by Him. Everything is transformed into something that points to eternity with Him, where what is today a cross will one day become a testimony of comfort and victory.