I doubt she dies in the second season, but know one knows what will happen to her.
As of July 21, 2010, the second season ended nearly 4 months ago and she is still alive. And she will be in Season 3, since the preview for that season focused on only her and about her having nightmare-like visions of the future (like the ones Anakin had in Episode 3).
Ahsoka Tano is 14 years old at the start of "Star Wars: The Clone Wars" and around 17 years old by the end of the series.
Rex's fate is a mystery to be revealed. As is Ahsoka Tano.
If you mean Ahsoka Tano, then she is the Padawan apprentice to Anakin Skywalker in Star Wars: The Clone Wars animated movie and following animated series.
Ahsoka Tano was created when the new TV series "The Clone Wars" was being planned.
Ahsoka Tano returns in season six, but only for a moment as a vision from Yoda.
Dave Filoni; the director on Star Wars the Clone Wars
No, Ahsoka doesn't have any sentimental relationships in Star Wars: The Clone Wars
Ahsoka Tano changed Togruta outfits during the course of Star Wars: The Clone Wars. But, both her outfits were a shade of brown.
Ahsoka Tano served as Skywalker's Padawan during the Clone Wars.
The name of his apprentice is Ahsoka Tano
Ahsoka Tano was born in 36 BBY (Before the Battle of Yavin), so during the events of "Star Wars: The Clone Wars," she would have been around 14-17 years old.
That episode is Season 3 Episode 16 "Altar of Mortis." (And actually, the only reason why Ahsoka turned evil was due to the living embodiment of the dark side of the Force corrupting her with a spell in an attempt to get Anakin to join the dark side)