"Enjoying the feast of that wicked man" is what brought upon the near holocaust.
Yet this wasn't a punishment, rather the natural consequence of their behavior.
As we previously mentioned, our attendance to Achashverosh's party was mandatory. However, the fact that we "enjoyed" being invited to the party showed that to a certain extent we started believing that the wolf's (Achashverosh) was important to our survival.. And it was precisely that attitude that removed us from the shepard's (Hashem's) special providence/protection, into the natural providence of the wolves.
The question is how did we come to make this gross mistake?
In order to resolve this question we must first delve and understand the following:
Rabbi Yanai explained "one shouldn't stand in a place of danger saying(thinking) that a miracle will be performed for him, because perhaps they (Hashem) will not perform a miracle. And if a miracle will happen, it's deducted from his merrits.
(יח)...וּבֵֽרַכְךָ֙ יְהוָ֣ה אֱלֹהֶ֔יךָ בְּכֹ֖ל אֲשֶׁ֥ר תַּעֲשֶֽׂה׃
(18) ...And Hashem your G-d will bless you in all that you will do.
(כב) בִּרְכַּ֣ת יְ֭הוָה הִ֣יא תַעֲשִׁ֑יר וְלֹֽא־יוֹסִ֖ף עֶ֣צֶב עִמָּֽהּ׃
(22) The blessing of the Hashem, it that makes (one) rich, And toil adds nothing thereto.
The fact that it's "Hashem's Blessing that makes (one) rich" is not only because our sustenance depend only on Hashem. But also, that bnei Yisrael's existence is in-itself unnatural aka above nature. And therefor our livelihood comes directly from Hashem.
The fact that Hashem commands us to work is only because He wants us to make a vessel to contain His Blessings, but not that our works draw down the Blessing.
And that's where we erred.
We confused the need of our own handiwork to be the source of our existence.
So when we were invited to participate in Wolf's (Achashverosh's) party we mistakenly believed that by attending we will increase our odds for physical survival. And that removed us from the miraculous providence of the shepard (Hashem).
Two Types of Miracles
And that's why the salvation miracles of Purim differ from the salvation miracles of Chnukah.
To better understand let us examine the two types of miraclous conduct:
1- Open Miracle: Nature is suspended. Hashem is Openly revealed. All recognize that this was nothing short of a miracle
2- Hidden Miracle: the miracle is enclothed within the garments of nature to the extent that the miracle seems to be ... just another natural event. or even completely
unrecognizable.
As brought in the following Medrash:
(ד) לְעֹ֘שֵׂ֤ה נִפְלָא֣וֹת גְּדֹל֣וֹת לְבַדּ֑וֹ כִּ֖י לְעוֹלָ֣ם חַסְדּֽוֹ׃
(4) To Him who alone Does great wonders, For His mercy endures for ever.
לעושה נפלאות גדולות לבדו. וכי אחר עשה עמו דבר שהוא אומר לבדו אלא הוא לבדו יודע מה פלאים עושה. כיצד אדם נתון על המטה והנחש לפניו על הארץ בא לעמוד הרגיש לו הנחש מלפניו ואינו יודע מה פלאים עשה הקב"ה עמו... ומי יודע הקב"ה לספר נפלאותיך. א"ר אלעזר אפילו בעל הנס אינו מכיר בנסו שנאמר לבדו. וכדדרש רב יוסף מאי דכתיב (ישעיה יב א) אודך ה' כי אנפת בי. במה הכתוב מדבר בשני בני אדם שהלכו לסחורה ישב לו קוץ לאחד מהם התחיל מחרף ומגדף לימים שמע שטבע ספינת חבירו בים התחיל מודה ומשבח. לכך נאמר (שם) ישוב אפך ותנחמני:
The Novelty of the Purim miracle is that it shows that Hashem is not limited to supernatural conduct. And that nature itself is not neccessarly an obscurment
But rather that nature itself is a can and should act as a channel for
G-dliness.
From all the above we can understand Ester's conduct in approching the king
1-Fasting and davening - The blessing of the Hashem, it that makes (one) rich
2-Physically approaching the King - And Hashem your G-d will bless you in all that you will do