The 'Glee' star releases her record 'Louder' this month and says music has been her ''therapy'' but she still finds it difficult to listen to the track 'If You Say So', which is about Cory, who was found dead in his hotel room in Vancouver, Canada, in July last year, after an overdose.
Lea told Billboard: ''It has both sides of the spectrum. Listening to it, it's therapeutic and difficult. It will always represent the most devastating thing that's ever happened to me in my whole life.
''But at the same time, music is therapy. It has been therapy for me in the entire grieving process and in my entire life.''
The 27-year-old singer says she has to ''acknowledge'' what she has been through and claims another song on the record, 'Cannonball', represents finding strength and hope.
She said: ''These are the two sides of my life right now. The grief, but also the search for strength and hope. I really wanted those two songs to bookend the album. Really let everyone know where I'm at.''
'Louder' will be released on March 17 and Lea is already looking towards her second album after completing her debut last summer.
She said: ''I'm already thinking about what I want it to look like. This record is such a strong representation of what the last two years of my life were like and I don't know what's next for me in my life. But I can't wait. Making music is so incredible, you tell the story of your life through music. I plan on it being very happy, very bright. Maybe not as dark.''
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