You might want to work on finding another descriptor. I just checked Urban Dictionary and every definition they have agrees with my general understanding that "party girl" doesn't really refer to a gal who likes to hang out and socialize with her gal friends. It generally suggests sex, drugs, and low personal standards. http://www.urbandictionary.com/define.php?term=party%20girl

Edit: You might try looking for a word more like "socialite".