You ask for some way of completely eradicating irritability. The inclination to irritability is given us to use against sin, and we were never meant to use it against our fellow men. When we do, we act contrary to our true nature.
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.
If the highest aim of virtue is that which aims at the advancement of most, gentleness is the most lovely of all, which does not hurt even those whom it condemns, and usually renders them whom it condemns worthy of absolution.
Pray simply. Do not expect to find in your heart any remarkable gift of prayer. Consider yourself unworthy of it. Then you will find peace. Use the empty cold dryness of your prayer as food for your humility. Repeat constantly: I am not worthy; Lord, I am not worthy! But say it calmly; without agitation.
The kingdom of God is always present for him who desires and wills it. When a man's disposition and way of life are like that of an angel, most assuredly this is the kingdom of God. For God indeed is said to rule as King when nothing worldly meddles in the governing of our souls and when in every respect we live not of this world. This manner of life we have within us, that is to say, we have it within us when we desire and will it. We do not need to wait a long time, or until our departure from this life; instead, faith and a God-pleasing life which accompanies faith are very near us.
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.
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.
When God, using our conscience, calls us to righteousness and yet our self-will opposes Him, He respects our freedom and lets our own will be done; but then, alas, our minds grow dull, our will slack, and we commit iniquities without number. On the other hand, the fruits of the spirit are soon granted to them who follow the commandments of Christ our Lord.
Remember that a good action is always either preceded or followed by temptations. God permits this so that the virtue, exercised in that particular action, may be confirmed, consolidated, steeled.
I suppose that it is sometimes better to fall oneself and rise, than to judge one's neighbor; because one who has sinned is incited to self-abasement and repentance, while he who judges one who has sinned becomes hardened in an illusion about himself and in pride. Therefore everyone must guard himself, as much as possible, so as not to judge.
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.
Ponder the truth of Christian marriage: man and wife are one flesh! Does it not follow that they must share all their possessions? And yet you two haggle over this property! And why? Because of words!