You are extremely skeptical of how one day he wanted to go back to OW and found an apartment to the next day saying the right things to stay in the house, right?how do you flop from going back to your affair partner of 2 years one day to the next being totally committed to rebuilding your M?
He said all the right things to get the vacation he wanted. He got it. And came home and said he wanted his mistress back and he was in love with her.
Do these things align with your core values?
I get that you feel empowered to ask him to leave....
But may, do you have any boundaries? What are your boundaries if you do? How do you enforce them?