herpes - is he lying?

Don't know if I have it or not since I'm still waiting for the test to come back.  I've been with my boyfriend for almost 3 years and he says he has been faithful.  I'm thinking he's full of shit.  From what I've read it can be dormant in your body for years.  How slim is the likelihood that one of us contracted it from a previous partner and my first outbreak is just happening now?