Of course your behavior is justifiable.
That's not the question.
The question is, "is it helping?"
It's easy to justify our mood or our actions based on how we've been treated by the outside world. Justification isn't the goal, though. It's effectiveness that matters.
We get to pick how we act, and it seems as though choosing what works, choosing what makes us happy, choosing what makes the world the place we want to make it–these choices are more useful than any justification we can dream up.