Disturbing social media posts appear to show a pattern of bizarre fixation by the alleged gunwoman who shot at Rihanna’s $14 million mansion in Beverly Hills while she was home Sunday. Police identified the suspect as 35-year-old Ivanna Ortiz , who was booked on suspicion of attempted murder. Authorities said Ortiz is originally from Florida. In the weeks leading up to the shooting, Ortiz posted a series of erratic messages and videos on social media that referenced several celebrities — most