Dianna Agron finds it hard to process deaths of tragic Glee co-stars Dianna Agron says the memories of her late Glee co-stars Cory Monteith, Naya Rivera and Mark Salling remain vivid. 16 August 2025 Dianna Agron still finds it hard to process the losses of Glee co-stars Cory Monteith, Naya Rivera and Mark Salling. Dianna Agron has fond memories of her late Glee co-stars The 39-year-old star played Quinn Fabray in the TV series from 2009 until 2015 and revealed how she thinks that her cast mates - who all suffered untimely deaths - continue to "feel so present".