Rihanna's Ex-Accountants -- She Screwed Herself Out of Millions!

Rihanna's Ex-Accountants -- She Screwed Herself Out of Millions!: Rihanna's ex-accountants just fired back at the R&B singer's lawsuit against them, claiming the MILLIONS RiRi says she lost was her own fault and they had SQUAT to do with it. If you recall ... RiRi sued her former accounting firm -- Berdon LLP…