From *The Catechism of the Catholic Church, *#1457:
“According to the Church’s command, “after having attained the age of discretion, each of the faithful is bound by an obligation faithfully to confess serious sins at least once a year.” **Anyone who is aware of having committed a mortal sin must not receive Holy Communion, even if he experiences deep contrition, without having first received sacramental absolution, unless he has a grave reason for receiving Communion and there is no possibility of going to confession. **Children must go to the sacrament of Penance before receiving Holy Communion for the first time.”
The Sacrament a person in mortal sin must approach is the Sacrament of Confession. More graces will come through abstaining from Communion than receiving it – particularly if you have a deep desire to receive Communion. It is an old axiom that longing to receive the Eucharist is very powerful penance.
Your rationale for receiving is poignant but, according to the faith and discipline of the Church, the matter is not one of personal discretion. I would advise anyone who has been receiving Communion in a state of mortal sin to confess it forthwith, be done with it, and not do it again.