The Boys episode 7.
I've been wondering the same thing Tasha after I rewatched the series. I'm wondering if she did cheat on Butcher and when she came of of the office, she thought "what the hell did I just do". That's why she had that look on her face. Then she probably found out about the pregnancy afterwards and that's why she went to the bench that day to think about what to do next . Or we're definitely wrong and she did cheat on Butcher🤷♀️ I guess we'll get the answer in season 2.