They will remove this person from your life in one way or another, like making communication almost impossible all the way to possibly harming the individual.
There’s also different terms to monogamy. I’ve found that sometimes things aren’t so black and white.
It depends on when this relationship was formed. If it’s a new relationship from this life, you probably have a pretty good idea of the terms. It’s difficult to stay loyal if you are not spiritually open enough to have a full experience. I have seen cases where you can be led to another physical individual to help you open up. Not sure if that was monogamous or not.
The Gods are pretty forgiving, just as long as you keep working on yourself. If you do not, they may give you a big slap in the face down the line. They’ll do it in the nicest way possible, but nevertheless...