Our new series "With Friends Like These" I detail cases where friends turn upon friends - and become deadly. The first is a case of high school jealousy. Kirsten Costas is attacked by a classmate in Orinda, California. Kirsten Costas (left) and Bernadette Protti (right) were classmates at Miramonte High School in Orinda, California. Bernadette became obsessed with Kirsten and wanted to be included in her circle of popular girls. Today's sponsors: Malicious Life Podcast Opinion Outpost - www.opinionoutpost.com/ONCE to earn rewards for completing surveys. Links to help with Hurricane Harvey relief: American Red Cross - text HARVEY to 90999 to give a $10 donation or online at www.redcross.org.  The Humane Society - www.humanesociety.org Recommendations for other true crime podcasts: Kiwi Crimes (New Zealand Crimes) Canadian True Crime S'laughter (UK Crimes)