OP, you are mistaken. Read the Compendium of the Catechism of the Catholic Church:
(The numbers refer to sections in the Catechism which give more detailed answers):
Underline is mine, of course.
*292. What are the fruits of Holy Communion?
1391-1397
1416
Holy Communion increases our union with Christ and with his Church. It preserves and renews the life of grace received at Baptism and Confirmation and makes us grow in love for our neighbor. It strengthens us in charity, wipes away venial sins and preserves us from mortal sin in the future.*
The fact that Holy Communion wipes away venial sins of course brings up an obvious question:
*306. Why can venial sins also be the object of sacramental confession?
1458
The confession of venial sins is strongly recommended by the Church, even if this is not strictly necessary, because it helps us to form a correct conscience and to fight against evil tendencies. It allows us to be healed by Christ and to progress in the life of the Spirit.*
In other words, the Church does not teach that someone who receives Holy Communion at daily Mass ought to go to confession more often than Catholics who only go to Mass and receive Holy Communion on Sundays. Nowhere is the recommended frequency of sacramental confession linked to the frequency of Mass attendance.
A Catholic aware of having committed a mortal sin is not properly disposed to receive Holy Communion and should normally refrain from receiving until he or she is able to be absolved by sacramental confession. A Catholic who is only aware of having committed venial sins ought to pray the entire Mass reverently, including the Penitential Rite, so as to receive Holy Communion in the manner the Church has proscribed. It is not necessary to confess sins before every reception of Holy Communion. (There are even confessors who will not permit such frequent confession of venial sins by a typical penitent, lest the penitent become scrupulous or begin to take the sacrament for granted in some way.)
Go ahead. Go find your mom and tell her that you were mistaken about what the Church teaches, and she was right. She ought to ask her confessor how frequently he thinks she ought to go to confession, and you ought to refrain from giving unsolicited spiritual direction to someone who is not in need of admonishment (and admonishment from you) about something that is not sinful.
To soften that–find someone to be your spiritual friend, to talk about these things. Better yet, get a spiritual director. Your desire to consider these things seriously and out loud is an excellent impulse. It’s just that you and your mom probably aren’t a particularly good fit for that. (Not unusual; don’t worry about it…)