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.
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.
If you wish to be delivered from shameful passions, do not behave with anyone familiarly, especially with those toward whom your heart is inclined by a lustful passion; through this you will be delivered also from vainglory. For in vainglory is involved the pleasing of men, in the pleasing of men is involved familiarity of behavior, and familiarity of behavior is the mother of all passions.
The joint prayer of husband and wife is a great force. That may be one of the reasons why the enemy is trying to get both of you to break this excellent habit. [This is] one more temptation which God permits so that you should learn to overcome it and come out of the testing stronger than before!
Do not judge and do not belittle anyone, because from this the heart grows faint and the mind is blinded, and from this, negligence appears and unfeelingness of heart is born. Keep ceaseless vigil, learning in the law of God, for through this the heart is warmed by heavenly fire, as is said: 'In my meditation a fire was kindled.'
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.
You must flee from sensual things. Verily, every time a man comes close to a struggle with sensuality, he is like a man standing at the edge of a deep lake, and the enemy throws him in whenever he likes. But if the man lives far from sensual things, he is like one who stands at a distance from the lake, so that even if the enemy entices him in order to throw him to the bottom, God sends him help at the very moment that the enemy is drawing him away and doing him violence.
Acquire humility, which scorches the demons, obedience, which opens the door for the Son of God to enter a man, faith which saves a man, hope which makes him unashamed; and love which lets not a man fall away from God.
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.
Do not attempt to assess the quality of your prayer. God alone can judge its value. To us, our own prayer must always appear so poor an effort, so inadequate an achievement, that the cry of the publican spontaneously rises from our lips.