From my own experience virgin females are not choosy when it comes to selecting a partner and in  captivity mate readily with the first male I introduce them to.  They may judge the male's performance but DON'T kill those they don't like, contrary to what you may have heard in a popular documentary.

Females only mate once in their life but males are either not very good in distinguishing between a female that has mated already and one that is virgin, or they don't care, they will keep trying whenever they spot a female.  Females deter such pesky lovers in a number of ways. In the first instance they will just ignore him or walk (jump) away. If this doesn't work the female may raise her abdomen and move it from side to side as a clearer sign of her unwillingness to mate.  It may take a while, and the male may make several attempts, but eventually he will give up and look for greener pastures. 

Do males get eaten at all ? Yes, if females are hungry and have mated, males can become food, in particular if they are not aware of a nearby female and therefore are unprepared for an attack. 

Do females eat the males they mate with ? No, I have never seen that happening, and I don't think there is enough opportunity for this to happen either. After the mating is complete the male usually jumps off quickly and the female is occupied by rearranging her abdomen which has been twisted by 180 degrees.