The most important thing during illness is to offer to God patience and thanksgiving for His merciful visitations. Sickness purifies sins and gives one time to meditate on the past.
Most people desire and seek after prosperity in this life, and they strive to avoid sorrows. While that seems very good and pleasant, constant prosperity and good fortune do a person harm. He falls into a variety of passions and sins, and angers the Lord, while those who live a life of sorrow come closer to the Lord and more readily attain unto salvation, for the Lord called the life of happiness the broad path. The wide gates and the broad way lead to destruction, and many there be who take that way (Matthew 7:13). It is the narrow way and the strait gate which lead to life eternal, and few there be who find it (Matthew 7:14). Thus, according to His love for us, seeing the possible benefit [of sorrows] to those who are worthy, the Lord moves many off the broad road and puts them on the narrow, sorrowful path, so that in [their] patient endurance of sickness and sorrow, He might effect their salvation and grant them life eternal.
You are, I am sure, aware that for you penitence is now no longer limited to disclosing your sins to your confessor, but that you must now bear your sins in mind always, until your heart nearly breaks with their ugly load; and would break, were it not for your firm faith in the mercy of our Lord.
Remember always that, once we have decided consciously to strive after righteousness, we cannot escape catastrophes and sorrows, no matter where we are.
The enemy constantly endeavors to awaken in the abyss of the human heart a great turmoil about trifles. This is one of his tricks to blind our soul to the sun of truth, Christ our Lord, hidden in the heart's core of every one of our neighbors.
Bear this in mind: the Christian life is an unending spiritual fight. The wily enemy cleverly uses snares and arrows without number. Before some of us he spreads the lure of worldliness, the outer pride of pomp and circumstance, the cruder lusts-the lusts of the flesh. But those of us who are not attracted by any of this he leads up on to the peaks of subtler prides. Having got us there-to the high country of self-esteem-he causes a dark mist, the mist of the subtlest prides, to enshroud our intellect. Then he leads us, his blinded slaves, away from God, without our even suspecting it. Mark this too: it is not very hard for the simple sinner to come to hate his foul life and, leaving it, to fling himself on the mercy of God; but it is very hard for the subtler sinner-the self-sufficient one-to let a ray of divine love pierce the leather jacket of his self-righteousness... Humility is the only weapon that wards off all attacks, but it is difficult to fashion, and the art of using it is often misunderstood, particularly by those who lead an active, worldly life.
Many do good actions, but neglect the mind; they know nothing of the spiritual contests, the victories and defeats. They neglect the mind which is the eye of the soul.
According to the teaching of the Fathers, any impression which, touching the heart, fills it with a great irritation, must come from the region of passions. Therefore impulses which spring from the heart should not be followed at once, but only after careful examination and fervent prayer. God preserve us from a blind heart! It is well known that passions do blind the heart and screen the shining sun of the mind that we should all strive to gaze at.
In answer to your question as to what constitutes a happy life, whether splendor, fame and wealth, or a quiet, peaceful, family life, I will say that I agree with the latter, but will add the following: A life lived in humility and with an irreproachable conscience brings peace, tranquility, and true happiness. But wealth, honor, glory and exalted position often serve as the cause of a multitude of sins, and such happiness is not one on which to rely.
A life lived in the world can be as good, in the eyes of God, as one spent in a monastery. It is indeed only the keeping of God's commandments, love of all, and a true sense of humility that matter, wherever we are.
Keep your conscience keen and bright, and refrain from hankering after, or expecting, consolation. Leave that to God. He knows when, where, and how to give it to you.
Pray that you may be granted the grace to read the Fathers with the right understanding, the grace to live up to the standards they put before you, and the grace clearly to see your own frailty. You will not long be left wanting and waiting. God will give you help.