Leave them to sort out their own mess.

You close the zipper, shrug and raise an eyebrow, but Emily seems to have completely forgotten about you anyway. She screams at her husband, slaps him and kicks him and has gotten completely out of control.

It seems to you that this was not exactly a happy marriage before this evening, and that the invitation has accelerated whatever issues the two were having before. In a way, you must agree with Emily: Didn't seem like a smart idea for them to come here. Or maybe it was for the best.

In any case, none of this is your concern. You leave the two fighting and continue your own way.