Anger gets you out the door. Purpose gets you through the whole run.

Anger is excellent fuel for the first mile and useless after that. It burns hot, it lights easily, and it runs out at roughly the moment the hard part begins. What carries you past that point is a reason you would still give on a calm day, when nobody has wronged you and there is nothing to prove.

If something you are doing started in resentment, that is fine, but check it now. Ask what you would still want from this if the person who set you off vanished from the story. Whatever survives that question is worth building the rest of it on.