Haman the Ungrateful

As R Shalom Arush points out, Haman's evil lies in his not being satisfied with his life. Haman says in Esther 5:13:

וְכָל זֶה אֵינֶנּוּ שׁוֶֹה לִי בְּכָל עֵת אֲשֶׁר אֲנִי רֹאֶה אֶת מָרְדֳּכַי הַיְּהוּדִי יוֹשֵׁב בְּשַׁעַר הַמֶּלֶךְ

Yet all this avails me nothing, so long as I see Mordecai the Jew sitting at the king’s gate.

Haman had so much - supportive wife, many children, friends, high position, wealth, but he cared about none of it because he was eating himself up alive over another person. This is the essence of Amalek. Being ungrateful means you are seeing daily miracles and scoffing at them, belittling - which is what Amalek, Haman's ancestors, did after the miracles in Egypt.

My friend Mosheh Givental pointed out to me that we Jews go by three names: עברים - meaning we are boundary-crossers; ישראלים, we are Godwrestlers; and יהודים, we are thankers - Jew coming from Judah, whose name came from his mother's decision to stop pining after Jacob's love, after her lack, but thank instead for what she had.
The person known most prominently as the יהודי in the Tanach is Mordechai. Mordechai the grateful (though I don't know if we necessarily see this trait explicit in the megillah - what do you think?)

Hold him up against Haman the Ungrateful and contrast.

The joy and gratitude of Purim prepares us for the דיינו of Pesach. And that is freedom - where no matter what happens in our lives, we hold on to our inner practice of gratitude.