..and why would 'the lady' happen to be in the same car park at the same time as your wife, when she wouldn't even know if your wife would be there , ever again ?
Was 'this lady' to sit there all day waiting for your wife to arrive, or has she been spying on your wife's movements, from either inside or outside the hospital ?
I hope your wife was able to point the woman in the right direction , (to quote Pinz's favourite expression) 'in short, sharp, jerky movements' .
Nobody needs this obnoxious, stress related trickery when visiting hospitals. Most people are already stressed enough, due to the very reasons they are there in the first place.
The whole affair needs to be reported.