Iris Robinson's affair

Iris Robinson MP, and wife of Northern Ireland's First Minister, is a Pentecostal Christian. A taste of the state of her god-addled mind is given by her statement on television that both  murderers and homosexuals can "find redemption in the blood of christ" (whatever that may mean). Is it any wonder therefore that she attributes her romantic fling with a 19 year-old youth to a "mental illness", not, as many would be more inclined to describe it, as the sign of a still healthy libido in a healthy body.  True, the situation poses simple questions of morality relating to the age difference (she is 60), and the possible effects on her husband and marriage. Apparently her religion was unable to provide, as is so often the case, (vide abusive priests), sufficiently compelling guidance in these matters. It merely served to intensify her feelings of guilt after the event.
I am not a psychologist but is it possible that in cases like this religious belief is more likely to be the cause of mental illness & depression rather than a refuge from it?