I don't understand the sympathy for Bec. She is a nasty drunk who is as much a shit-stirrer as Gia and Juliette.
Bec does apologise afterwards. However, I have met a few people like this who are horrible when drunk, say really hurtful things, but expect everybody around them to forget it the next day and behave normally.
If this is a pattern of behaviour repeated many times, then everybody loses patience and sympathy. How many times can you say sorry and expect people to forgive?
So for me, Gia, Juliette and Bec are equally as bad but for different reasons.