Having also not been reared in a church which does not (at least in modern times) value or regard confession highly, and having read this thread with interest at the same time while examining myself to make my own confession tomorrow, there are a few things I want to share. Take them or leave them.
When I was Lutheran, one of my priests offered private confession and absolution. I took advantage of that as much as I could. HOwever, in the preparation to make confession, right before actually confessing, I would pray to the Lord that "I want to do better." To me, this sounds more like psychotherapy than it does confession. If confession, like all the mysteries, is to be a means on the road to the theosis then we need to clarify what theosis is. And theosis IS NOT, as Archimandrite George of St. Gregorios Monastery writes, simply becoming a better moral person. It is becoming like Christ, in everything. And, I think that is what many of us, if not most of us are trying to do in confession. We are aiming at moral perfection, not godly perfection.
And, perhaps this is mainly for those of us who are converts from a Protestant confessions (I really don't want to get into a cradle vs. convert controversy, just hear me out), I think a lot of us may have this belief when we go to confession that we are trying to appease this deity who is wrathful and hates sin. We approach the confessional with fear and trembling (which is fine as this is the Lord), but without the clear immediate realization that his mercy endureth forever, especially at the confessional! The confessional, to many, in my view, represents judgment and so we enter into a juridical mindset. Yes, we need to be honest and forthcoming with declarations of "I have sinned" but that should not requireus to think for a moment that God is only our Judge and no longer our Saviour. Surely, he is both.
There has been discussion here as to whether we should, in our confessions, go into the root of the problem since this is what psychotherapy does. Sin does have roots and, for many, one sin leads to another which leads to another creating a domino effect. We may not be consciously be aware of what it is. In my case, I know that my lack of attentiveness to my prayers and fasting is often the culprit that can lead to other vices and obstacles in the attaining of theosis. One sin gives way to another. As St. John Damascene writes in his On the Virtues and the Vices, "You should also learn to distinguish the impassioned thoughts that promote every sin...It does not lie within our power to decide whether or not these eight thoughts are going to arise and disturb us. But to dwell on them or not to dwell on them, to excite the passions or not excite them, does lie within our power." (Philokalia, vol. ii, p. 337)
Thus, we should be very aware of what the roots of our sins are even if we are unable to control when or when they cannot drive us to further sin against our Lord and God. But we can learn ways to combat how much they will influence the nous, the intelligence. With that in mind, confession is a therapy of the soul, but unlike modern psychotheraphy, it does not justify. And let's face it, many of us do try to justify it (I know I do). And we try to justify it because many of us see God in the Confessional only as the stringent Judge who goes by the letter of the 10 commandments. Is Christ no longer our Saviour? Of course, he is. That should never be an excuse for us to continue in our sin, as St. Paul says in Romans "God forbid!", but it should remind us that confession is not a juridical act and that the Christian life is not simply trying to be and live morally, but it is to become like our Lord in every respect. Yes, we have sinned and come short of the glory of God, but, thanks be to God, that's not the end of the story.
Just my thoughts. Again, use them as you will.