It is a word that you might say you felt after completing a challenge or something difficult that you invested a lot of time into and caused you significant frustration, and then going and destroying or getting rid of everything having to do with said challenge. For example, if you spent all year studying for a class and collecting notes and practice exams in preparation for the final exam and then at last when it's over you no longer need any of your notes and burn all of them. You might say "Ahh that was -------" And that burning your notes made you feel better. It's kind of like revenge against whatever caused you pain.
I suggest "catharthis", though the dictionary definition is more focused on expressing the emotion through art
Dictionary.com describes it as:
The purging of the emotions or relieving of emotional tensions
Another definition from Merriam-Webster
the act or process of releasing a strong emotion (such as pity or fear) especially by expressing it in an art form
You would say "ahh, that was cathartic"
Edit: you might also say "ahh, that was freeing", as in you've been freed from your emotions of anger and stress. Less powerful, but perhaps more accessible.
Perhaps you would just say:
"Ahh that was good riddance!"
1. the act or fact of clearing away or out, as anything undesirable.
2. relief or deliverance from something.
3. good riddance, a welcome relief or deliverance from something:
He's gone, and good riddance!