Following the death of "Glee" star Cory Monteith friends of his girlfriend, Lea Michele have grown concerned that the actress will never be able to come to terms with her boyfriend's death and revealed that she is filled with guilt.

Entertainment Wise reported that since Monteith's death nearly two weeks ago Michele has been questioning just how she will get through the pain of losing the actor and has been on an emotional roller coaster of highs and lows following his passing.

"It seems so unfair and impossible to process," a source told Look magazine. "She's furious one minute and wracked with guilt the next. I think she's wondering how she'll ever get over his death - and if that's even possible."

Monteith, 31, who was found dead in his Vancouver hotel room from a fatal mixture of heroin and alcohol, was cremated in a small ceremony attended by family and the actress last week in Canada.

The source described the sad moment when Michele found out about Monteith's death and reflected on how lucky she was to be surrounded by friends at the time.

The source said, "Lea had just got back from a holiday in Mexico when she got the call. She was with friends, thank God, because she went into shock. Her mum, Edith, dropped everything to be with her but there's nothing anyone can say at this point."

In her last interview before her boyfriend's death Lea Michele posed for the cover of the August issue of Marie Claire Mexico and opened up about her relationship with her co-star.

According to PopSugar, she told the magazine, "It's more interesting having a relationship with someone you work with because we get more attention because we play boyfriend and girlfriend on the show and we are also in real life.

"But he is the best person I know, he has made my life so incredible, and I am so thankful for him and not only to have him as a partner but also as a co-worker."

She continued, "It is important to have someone that supports you and encourage you, someone that makes you feel that you are unstoppable, that you can do anything in the world because you have him."

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