Is this cheating or fair play?

I am a 22 year old single gay-guy. i have a friend who is 29- married but her husband is in iraq. anyways, she wants me to stay with her while he is away which i do. i even went down on her, trust me, it was just that- we both knew it. but she prints out emails and i saw one with her hubbie and their relationship isnt going well. btw, they have a baby daughter born this year. i know she has a strong desire to be single, she loves when i take her out ofr dinner for some reason. lol, she even took me to a gentlemans club. ps, we live in the big ATL