OP I am so sorry you have been put into this situation. It fucks me off so badly that we are carrying on life as normal, then one day a bombshell like this hits and then WE have to be the ones to make the difficult decisions of life going forward. This to me is one part of affairs that gets to me the most.
No one here can give you the answer of what to do. We do not know your circumstances and this matters. It is not always just so easy to say ok that is it now, get out today, because we don't know your situation.
I found out about my ex's (first that I know of) affair in the morning of 18 December years back. It was the day we had planned to go Christmas shopping for the DC gifts. I had family staying from overseas and so I chose to just carry on as normal as I didn't want to spoil others holidays, my dc Christmas etc. It was not good for me, but I felt it was the only way. It was a dirty little secret I had to keep. Bit of a long winded way to say that the guests left on 3rd Jan and 4th Jan I was admitted to hospital having suffered a breakdown. I had not eaten in 10 days and the day I was admitted I could not even stand up.
So to the poster upthread, yes you can be diagnosed with PTSD for being lied to and cheated on. As I was.
As I was so fragile (I know this sounds pathetic, as I am a strong independent woman) but I was. I was in no place to make any hard decisions. It just was like my whole world had been thrown upside down in a space of time of reading one email.
So we stayed together and tried. For 5 years I tried. He didn't so much and when I caught him out again in the most blatent affair I knew I just could not do it again.
In the meantime though, I went for therapy, put away some funds every month, we had a joint business and I got that into my sole name, and got myself in order as deep down I knew it was a matter of time. I started to take care of myself before him and he didn't like that one bit. I vividly remember him asking me was I having an affair because I was now using body lotion! Talk about projecting. So in essence, I had unknowingly used that time to get my affairs in order. And good job I did as he become very nasty after we split and I know he would not have agreed to a lot of things after. I suppose I used his grovelling time to my advantage.
You do not need to decide anything right now. Do not feel pressure to do anything right now because other people did XYZ. You do what you need to do for you.
I'd block the ow, you do not need her 2c or opinion or excuses right now.
Please eat, drink and take it hour to hour at the moment.
💐