I didn't agree with the "out of town" thing either. The reason that she said that though is because we all watched my BIL go thru a very public EA/PA? a year or so ago, and my H finally had it out with his B, telling him that he didn't care what B was doing.... but don't be doing it in our home town. She was around for that mess (small town, close group of friends etc). Because she is my GF she is sensitive to the fact that H is hurting me, and was mentioning H's own advice. I wold rather have him in town so that I am aware what is going on. Watching him openly flirt with other girls hurts, because I don't get good affection from him now and I hate having our friends thinking he is "hitting on other women."
Most of us are about as happy as we make up our minds to be.