Resentment is a case in permanent preparation. The evidence gets updated. The closing argument is rehearsed in the shower.
It is devastating, and it will never be delivered, because the trial was never scheduled and the other party has no idea they are a defendant.
The cost is the preparation. Hours of it, spread across years, all of them spent in a room with somebody you would rather not be in a room with.
Dropping the case is not the same as saying they were right. It is saying the courtroom was yours, you were paying for the lights, and you would like the building back.