I have to agree with you ming
My ex GF (civvy) was totally the same with just one use of a Condom she would come down with a smelly pussy
this was with durex and pastane. no condom and no problem.
Also no problem with mates condoms. smell stopped and didnt come back either.
So I would suggest that it is a condom (irritation/reaction) that Sandy suffers from.
Oh and smelly towels are a massive turn off too
Also apologies if im not allowed to mention brands ..but its just a valid point im making.