What mistake did Ivan Ilych made his life chaffy? Attest by using direct quotes from the novel?

From Chapter II, “…he married because his social circle approved of the match. He was swayed by both these considerations: … it was considered the right thing by the most highly placed of his associates…”[1]  He lived to indulge others and usually this is a perfect way to flop.
“… he considered his duty to be what was so considered by those in authority… he attracted to people of high station…, assimilating their ways and views of life and establishing friendly relations with them…”2  He conformed the benchmark and only thrived to become a paragon pawn of those in high pedestal. He considered that the best authority is the achievers.
“…when obliged to be at home he tried to safeguard his position by the presence of outsiders…. The whole interest of his life now centered in the official world… and continued to flow as he considered it should do — pleasantly and properly.” 3  He escaped goat from his nagging and irritable wife by being workaholic. He tried to evade from the problems instead of facing it courageously.

He denied his spiritual life. According to Chapter XI, he was reluctant first of taking the communion but felt obliged when pleased by his wife. He lacked faith. As the saying goes, man does not live by bread alone but from the word of God. He is self-centered in a sense he followed the ontological good but not morally upright. He lost his dignity which is his morality.
2. What are the implications of death to spiritual malnourished like Ivan and Kanji?
Fear—for they are not ready; for they haven’t found the significance of their very existence. They feel that there is something missing that has to be found as acted by Ivan and Kanji. There very instinct told them so and this is their inner man. Man is physical, social, emotional and SPIRITUAL—which animals lack.
3. What made Ivan/Kanji succored while still in malady and agony?
In The Death of Ivan Ilych,
(a) “When the priest came and heard his confession, Ivan Ilych was softened and seemed to feel a relief from his doubts and consequently from his sufferings, and for a moment there came a ray of hope…”4 (b) through love and compassion showed by his sick nurse and by looking at him and (c) through the caress of his son.
In Ikiru, through kindness and plainness of Toyo, a young girl who works in Mr. Kanji Watanabe’s office; looking at her made him feel better. (Kurusawa, 1952)
4. “Yes, it was not the right thing …but that’s no matter. It can be done. But what is the right thing?”… 5
Forgiveness, acceptance and compassion. (The Death of Ivan Ilych)
Simple way of living and doing things superficial as it may seem but has a worthwhile impact to others which is charity. (Ikiru)
5. What are the moral lessons of the novel/film?
*  Success and happiness in life is not measured by career or material wealth as opined by many. Sometimes the most happiest and fulfilled person are the poor and uneducated portrayed by Gerasim and proven by Tolstoy.
*  Learn to balance your self. It’s not about career. Spend some time in simple things yet worth remembering. Life is short so use your life to the fullest.
*  Without God as a center of life, life is in vain.
Notes
1. Tolstoy, Lev Nekolayevich. 1886. Death of Ivan Ilych. Christian Classics Ethereal   Library http://www.ccel.org/ccel/tolstoy/ivan.iii.html (accessed March 11, 2009)
2. Tolstoy, Chapter II
3. Tolstoy, Chapter II
4. Tolstoy, Chapter XI
5. Tolstoy, Chapter XII