If we have emotional problems or illnesses God wants us to seek treatment for them - from a doctor or therapist or other professional if we can’t resolve tehm ourselves. This is the only true treatment, not an affair.
God does NOT, EVER, want us to have an affair or break our marriage vows, nor does He, EVER, want us to cause others to break their vows of marriage - or their priestly vows which are just as binding!
Marriage is a sacrament, Holy Orders is a sacrament, what part of that do you not understand? HE joins the couple who vow til death to each other, assuming the marriages are valid. HE anoints and ordains the priest who consecrates his life and chastity to His service.
Whatever the future possibilities of her annulment or his laicisation (which he clearly doesn’t seem to want to do anyway), for the present the couple MUST act on the presumption that her marriage is valid and his ordination is binding until such time as they hear otherwise from the Church.
To do otherwise is sin, they can’t be sure without Church confirmation that she IS free to marry - or that he is!