My husband dreamt about his ex😔

So my husband said he had a dream of an ex. He didn’t say which one. He said he needed some financial help and she offered. He refused because he’s married to me and knew it was wrong. So he kept telling her no. What does that mean? I’m so sad bc I never dream of an ex, does he still have feelings for her, does he think about her? I don’t know if I should ask him these questions or will I come off as insecure.