After discovering an inappropriate relationship, a strong indicator over the repentant nature of the cheater is how they handle that relationship going forward.
They must choose:
Is their marriage more important than this fantasy-fling or is this illicit relationship more important to them?
A cheater who stays “friends” with their affair partner is telling faithful spouses that they choose fantasy over the marriage. They are NOT repentant.
Keeping the relationship is revealing the cheater is STILL prioritizing their (or the affair partner’s) feelings over the faithful spouse’s.
In other words, their hearts are still in the affair. They have not dealt with the rotten core of their sin and are showing their unwillingness to do so.
Faithful spouse, save your breathe if this is how your cheater behaves.
It is time to move on from such a “marriage.” You cannot stay married–in a godly sense–to someone who continuously harbors adultery in their hearts. You do not have to stay tied to someone who is hell-bent on spiritual destruction (see Heb 10:26-27 & Mt 19:9).