I'd try to ask in a non-accusatory way and see what he has to say. It's just one sentence. It could mean that he's not trustworthy, or it could mean something entirely different. Before you throw away an entire relationship based on just one sentence, I'd try to understand his thinking first.
If you're worried that he'll try to mislead you about his intentions when you ask, just pay attention to whether he's simply sweet-talking or give honest, thought out answers. Pay attention to your gut, but after you have more information.
Last edited by VerticalMoon; 02-08-13 at 06:37 AM.
Reason: thought of more to add
“This planet has - or rather had - a problem, which was this: most of the people living on it were unhappy for pretty much of the time. Many solutions were suggested for this problem, but most of these were largely concerned with the movement of small green pieces of paper, which was odd because on the whole it wasn't the small green pieces of paper that were unhappy.” ― Douglas Adams, The Hitchhiker's Guide to the Galaxy