Greetings in Jesus Christ Our Lord and Savior,
According to Catholic theology, part of being sorry for our sins involves a firm resolution to sin no more. Even after Confession, we are not perfect and sinning (mortally or venially) is still a concern and a possibility.
However, when we say that we firmly resolve to sin no more we mean that we will try our hardest to not sin. We do not want to offend Our Holy God and so we are saying that we intend not to sin again. We shouldn’t be scrupulous and hold ourselves to a standard that we cannot meet and that God does not hold us to. However, it isn’t scrupulous to make a firm and concussion effort to not sin.
Holy Mother Church recommends going to the Sacrament of Reconciliation frequently. Don’t worry about venial sin. Do try to avoid it, but do not get discouraged when you sin. When I came back to the Church, I thought that I could be almost perfect right away. My mentality was bad and I had become scrupulous. Now I still always try to avoid sin, but I recognize that it is by humbly receiving God’s grace over time that we become holier. I hope that this answer helped you.
God bless and Mary keep you.