'Friends' star Courtney Cox believes that Jennifer Aniston is a true friend of hers as she has stood by her through troubled times."We've known each other for nearly 15 years now, we grew up together emotionally. I lost my father, Jen got divorced, and I had a baby," she told a magazine.44-year-old Courtney insisted that she felt "lucky" to have her 'Friends' co-star for a pal."We've been through huge life changes together. I can still be myself around her. We never judge each other, we support each other, but we're honest with each other too. I feel lucky to have her," said Courtney.Aniston, 41, who is also godmother to Courtney's four-year-old daughter Coco, vists her friend regularly and also spent her Christmas this year with Courtney and her husband David Arquette.