It's amusing really. Anyone can tell that she loves her father, and when her father died, it was definitely a big blow for her. Why would a girl like her USE HER FATHER'S DEATH LAWLAWL THAT EVILWITCH!!!111 to get what she want? Geez. Some people just REFUSE to admit that she might not been acting and thinking rationally then, and insist on using MANIPULATION as a reason.
And why put all the blame on Shirley? Lelouch had a part in returning that kiss. It wasn't as if he was forced at gunpoint to do it.