Pretty much the same elements in the case of Curad. Let daddy
analysis this situation for you bah.
Firstly, the impression B has in A when the both of them are
getting closer is more of a friendship than anything else. This is
shown by the fact that she isn't anywhere better than his ex,
therefore he rejected her with the context of excuse saying he
couldn't forget his ex. Ok... so be it. 
This girl definitely has a gnawing inferiority in her, which
creates a void of emptiness in heart. (Sh|t I am using the same
sentence again). She couldn't have him, therefore he goes try
relationship with other guys - hoping that someone could take over
the place eventually. In the end, none made it. Therefore she
always say, there is a place for him in his heart. 
Actually this girl unconsciously is using reverse psychology to
lure him to jio her. But as you can see, she has failed. What I
mean by reverse psychology? It simply means that she go with other
guys to try to make B do something about it if he likes her,
because if he do something, she will immediately accept. Sad to
say, as her quest went - I doubt B's impression of her will
continue to remain good.
If you ask daddy if B like her, I would say most probably no.
Because if he did, he would already do something and furthermore,
what she did - moving along with guys one after another - only
serve to futher destroy this impression B will have. 
Question 1
Whether she is a b|tch or flirt - it all lies in the eyes of a
beholder.
Question 2
Whether A and B will fall out because of her - I doubt so, unless A
is very subjected to woman's scheme. I doubt B will because of her
fall out with A, but if it did happened - most probably will be
because of A. 
Question 3
What should the girl do? The girl have been making mistakes for SO
LONG. All her love decision are totally screwed up. Unless miracle
take place, I doubt B will accept her. Its time to give herself
some *quality* time to think and reflect upon herself. She made
decision for the sake of making them - its damn screwed up. She
need to think about things, etc and see what she really wants. Once
she know for certain, etc - without giving up halfway - she has to
go for it. Or to give it up totally. Moving about to nowhere will
only serve to reflect upon her character that B will pout.

Cheers