I’m going to give you the benefit of my experience with a cheating spouse.
Just a bit of background. My H had a 4 year in person EA that he refused to admit to. I knew it was going on. Finally ended. Rugswept 100%.
Years later it’s now a typical midlife crisis affair. He’s kicking me to the curb after 25 years of Marriage to be with the OW.
My smartest move was choosing an amazing counselor during this nightmare.
My worst move was doing the pick me dance. I didn’t know about SI during the affair so I made some typical mistakes.
It took me 6 months of being on an emotional rollercoaster and dday2 to finally stand up to my H. During the 6 months between dday1 and dday2, I was smart enough to get a plan B together.
Long story short — when I found out he was still cheating — I had a very calm rational 1 minute conversation. My exact words were this: I am divorcing you. I’m sorry it has come to this but you have left me with no other choice. This marriage is over and you are free to be with the OW or anyone else you choose.
I left the room. I did not give him an opportunity to speak.
He then starts begging me to R. Dday2 when I found out he was cheating he had (for the millionth time) demanded a D. Of course I was shocked and blindsided because a few days before he was all in on reconciling.
I said no to R. I then told him he had to leave.
He still thought he was in control. 
I told him I was filing for D after the holiday season. New year. Fresh start. I had the mediators lined up and ready to go. I had a plan and was executing it.
He was stunned. Never expected it. Thought he could sweet talk his way out of the mess.
He saw a side of me he never expected. I did the hard 180 and did everything to protect myself.
In short I saw signs of potential and held off on filing for D. It was on a day by day basis initially. I required a post nup to even consider reconciling w/ him. And for the first year of R it was very difficult.
We are one of the lucky ones who have happily reconciled. But only because my H changed.
