Esmerelda this may be the sort of questions JWs ask but I had no realization of this, I was born in. I think they are highly inappropriate and they have set of some alarm bells, even more so because you are a single woman.
They were trying to work out your support network and I don't think I am exaggerating when I say that I think this is the very thing a pedo would do. Even if it is more innocent they want to work out how easy it is for them to draw you into the cult and make you feel dependant on them (the JWs).
A lot of JWs are gossipers as well and don't expect that the information you give them will be kept to themselves.
Steer clear of this couple.
In a larger group I would normally suggest that you spend some time observing others and see how they interact with each other but it is different in the JW world because there are many who put on a fake front but typical of a cult.