Is there any “Next” logical step in this process??
What do you mean by this question? IMO you have two options:
1. You go along doing what your'e doing and wait to see if her affair fizzles out and maybe just maybe she decides that plan B was not so bad after all.
2. You decide you had enough of her selfish BS and you file for divorce.
Both options suck, but one makes you look weak and one makes you look strong.