Being deceived by WAW, in need of some coaching

[skr4luv]

Things are about to change.

Yesterday was her last day of work at the office and today she's
transferring to a new location.
Knowing she had almost nothing to do on her last day of work,
I checked the car mileage the day before. Last night when I came
home I saw that the mileage increased by 50km . Her office is
only about 5km away, so I was sure she went somewhere.

She was in a good mood when she saw me. Kissed me as I walked
in and even handed me a present (a special coffee mug).
After the kids went to sleep I calmly asked her where she went.
Of course she denied it at first, insisting she only went to
work, but later admitted she met OM for lunch at the mall.

So I told her this isn't going anywhere, I'm not willing to
share her with anyone.
She said, she thinks that everything is working fine between
us if I would just let those things go and look away.
I said I don't wanna get played and I'm tired of her lying, we might as well split now.
First she expressed some concerns that she doesn't want me to get depressed and have everyone blaming her for that.
I assured her that won't happen, that I will be able to move
on in time.
She again said something about having a hard time letting
go of OM, that her feelings are too strong for him.
She understands that taking a time off will help me go thru
it. I made it a point that I'm going to stay with the kids
when I get back and also suggested that she can already move
away, even go to the OM, as long as I'm still here (have to
work for two more months after resignation).

This whole situation is making me feel uneasy and sad to be honest. I wanted it to work out, and I thought she was
making baby steps towards the same goal. If I haven't come across this board, I'd probably have forgiven her for meeting with OM and praticed more patience for her recovery.
I'm now pushing her towards the OM and I have to focus on
a future without her. I'm unsure how to act around her now.
Should I be indifferent and upbeat, as if I'm already
moving on. Or express how disappointed I truly am that she
couldn't let go of OM?