You people are missing a valid point: sometimes people just don't like someone... I couldn't stand her mainly for the reasons that Abominamatrix has stated really well, and also because I didn't find her character to be remotely interesting which is my opinion (there doesn't have to be a reason she just wasn't interesting).

Also something else, people say she sacrificed herself. I never noticed that, I personally only saw her go off optimistically thinking she was going to succeed, saying to Cloud not to worry- this did not strike me as going off to sacrifice yourself. It was also plain stupid if she thought sacrificing herself was the case because with a group she'd have time to complete the prayer- if she thought she'd die she'd have no way of knowing whether she'd have time or not.

So I consider her not to have sacrificed herself as I can't remember any evidence for that, I consider her to have tried and died trying, without expecting there to be much risk.