I can't imagine that Islam offers a woman anything in any life. Her biggest reward might be getting away from the psychopaths who sent her to do this.
I'm going to guess the woman was subject to honor killing, and they gave her a choice between being stoned to death or becoming a suicide bomber. She figured death-by-bomb was likely to be quicker and less painful.
There was one muslim female involved in the Beslan school massacre She was from Chechnya. Supposedly, she lost two brothers to the Russians.