[She doesn't get angry this time. She asked for this information. She can't really accept that it's true, but for now she will accept that he believes he's telling her the truth.]
I've never cheated on Piotr. [She says this calmly, but firmly. She can't imagine doing that to him. But she couldn't imagine this situation either. The thought that it only took her at most a couple of months to change her mind is... She's not even sure what that is.]