Actress Lea Michele and actor Cory Monteith
Actress Lea Michele and actor Cory Monteith

American actress Lea Michelle is reportedly "devastated" at the sudden death of Glee co-star and boyfriend Cory Monteith.

"She [Lea Michele] is absolutely hysterical and completely inconsolable," a source close to the actress told Hollywood Life, "She is devastated beyond belief."

Monteith, 31, who played heartthrob Finn Hudson in the hit Fox television series, was found dead in a room at the Fairmont Pacific Rim hotel in Vancouver, Canada.

"We ask that everyone kindly respect Lea's privacy during this devastating time," a spokesperson for the actress told People.

Soon after Monteith's death news was confirmed, #PrayForLea, #StayStrongLea and #RIPCoryMonteith were all trending topics on Twitter. Celebrities and Monteith's co-stars also took to the micro blogging website to react to his untimely death.

The 26-year-old actress met Monteith on the sets of Glee back in 2009 but their friendship blossomed into a relationship only later.

Michele, who plays on-off girlfriend Rachel Berry in Glee, talked about the couple's relationship in Marie Claire's January issue.

"I don't even remember a time when he wasn't my boyfriend," she said, "No one knows me better than Cory. No one knows what it's been like to go through this more than he does. Feeling like you have that net underneath you allows you to jump higher and go farther. He makes me feel like I can do anything. For the first time in my life, I feel really, really settled and happy. I feel like the luckiest girl in the world."

In April, Michele publicly supported Monteith, following his decision to check into rehab for substance addiction.

"I love and support Cory and will stand by him through this," she told People, "I am grateful and proud he made this decision."