I ended a relationship I knew was not right for me, and it still wrecked me. Why does doing the right thing hurt this much?

“I am weary with my groaning; all the night make I my bed to swim; I water my couch with my tears.”

This is one of David's laments, written in the middle of the night, and it does not resolve quickly. The picture of a bed soaked through with tears is deliberately excessive, the language of someone with nothing left to perform for anybody. Scripture keeps prayers like this in the book, which means grief this raw is not evidence that you decided wrongly or that your faith is thinner than it should be.

“Now no chastening for the present seemeth to be joyous, but grievous: nevertheless afterward it yieldeth the peaceable fruit of righteousness unto them which are exercised thereby.”

Hebrews was written to believers tempted to go back to what was familiar because the cost of staying had grown heavy. The writer concedes the obvious, that no discipline feels good while it is happening, and then insists there is fruit afterward for those trained by it. He does not shorten the painful stretch or talk you out of it. He tells you it is not the whole story.