Ouch

So how do I take this?

I spent a night this weekend with a female friend. It was someone I hadn't seen in a while, and we just hung out, ate some food, and just had some fun. Anyway, beforehand a co-worker overheard us making some final plans, and talked to the lady after hearing that. She asked first if we were dating (of course--two single people spending time together clearing must be dating), and when told we aren't, made a comment to the effect of, "Ok, I don't want you to get your heart broken."

So, my friend told me this, so she obviously isn't too worried about that. But, what does that say about my co-workers opinion of me? How am I supposed to take that?