Was Antigone cruel to her sister?

Even though Antigone was presumably cruel to her sister, she was actually looking out for her best interest.  It is not possible for a sister to go to such means to bury her brother yet be genuinely cruel to her own, very alive, sister.  There are several times in the play when Antigone says very questionable things to her sister.  For example, Antigone first denies that her sister had anything to do with the crime.  She does this in a way that appears that all Antigone wants is to be the center of attention.  Also, later in the play Antigone states that she is the last member of her house, when Ismene is clearly still alive and well.  As the readers understanding of the play develops, he understands that Antigone is must be purposely trying to make Creon forget about her sister by completely excluding her from the situation.  Also, Antigone's clever personality contributes to the readers understanding of Antigone and her motives.  In conclusion, Antigone cared more about the safety of her siblings than the fame of her death, therefore the only explanation of her cruelty towards Ismene is that she was trying to stealth her from the prosecuting eyes of Creon.