You have nothing to lose by calling.  The worst that can happen is that she will  not answer.  If that happens, you know she is prob no longer active, so move on.  If you have an email address for her, email her.

Swim

Call her. (or email her) If she is not available she will probalby not answer and just ignore your call. If she is retired, her phone will probably be disconnected, and you won't know that unless you call it.

There are many reasons an ad is not posted. Sure it might mean that she is taking a hiatus or retired, or went UTR. But it is usually something simple like the ad just expired and she hasn't put up a new one. Or she has ads in multiple places (as many ladies do) and just because the one you have seen in the past is down, does not mean all her ads are down.