The guy I've been dating for a month just told me that his ex-girlfriend works for the same company in the same building. She works in a different department but their paths do cross occasionally. They've been broken up for over a year but dated for a long time before that, so they have a lot of history together. I don't really feel threatened by her (look wise), but I know that sometimes old feelings just come up again. Now obviously I can't ask him to quit his job or anything like that but... should I be worried?