Q: Can a Catholic who’s not ‘married through the Catholic Church’ go to confession?
 
A: If someone is a baptized Catholic and are in a marriage that was not through the Catholic Church, they are not able to receive absolution.  This is based on the belief that ‘contrition’ can’t be true contrition if the person clings to one or more sins and shows no intention to ‘amend their lives’.  The situation can be resolved by getting their marriage ‘blessed’ or, better said, ‘validated’ by the Church.  Until that the couple is validly married in the Catholic Church they CAN GO to confession but the priest is not permitted to grant absolution, the sacramental forgiveness of their sins. 

I say it that way because many people come to confession not realizing this and begin confessing their sins.  They may tell the priest they are not married through the Catholic Church or the priest may suspect this to be the case and explain the situation to them and deny them absolution.  The priest is required to do this.  He is not permitted to grant absolution.  Even so, they often feel some spiritual, psychological or emotional benefit from ‘having confessed their sins.’  Another way to say that is: ‘repenting feels good’.  Something is changed in the person; some emotional or psychological burden feels lighter just from making a good examination of their conscience and telling the priest their sins.  Nevertheless, absolution of their sins is withheld with the hope that it will lead them to a complete contrition and to pursue a valid Catholic marriage.