Me and partner are separating after 15 years together (due to her affair) and two young kids. I am living in the house, she has moved out to her mums.

She comes round to help with kids school drop and pick ups and night time routine before leaving. She contemplated coming back whilst we are selling the house but she says it’s “too awkard”.

My problem is that she is still actively seeing the person she had the affair with. I know for a fact that they run together a few mornings a week before she comes to our house for kids. She may be seeing him in the evenings but I have no way of knowing this. He was married so I don’t know if he is still in that relationship or not.

I want to try to be amicable for the kids but i am so full of rage that she has chose someone else over me and is activity pursuing him now we are separating. Hurts so bad and feels so cruel. I hate that he will be getting a side to her that I only got. Or he will be intimate with her in a way that only I was.

Bit of a rant I know but how do I rationalise this?