Taylor Swift says writing her new album was a ''roller coaster''.

The 22-year-old singer thinks her fourth studio album 'Red' perfectly captures the highs and lows of her turbulent love life over the past two years, from bitter break-ups to her new romance with Conor Kennedy.

Taylor told Rolling Stone magazine: ''I went through a few roller coasters. Trying to chronicle each step of the way was challenging, because you go to some really dark places with the lyrics.

''Then in the next track, you're talking about how amazing it is to meet somebody new.''

The singer - who wrote her last album, 'Speak Now', by herself - chose to collaborate with huge producers such as Max Martin and Dan Wilson on her latest work, and learnt much during the process.

Taylor added: ''I felt like an Apprentice. They taught me so much about melodic sense, and they let me do what I love, which is the lyrics.''

While she wrote the songs with other people, Taylor still penned all the lyrics, about the ''mystery'' of love, herself.

She added: ''I know general things about love. How to treat people well, what you deserve and when to walk away.

''Other than that, love is a complete mystery - and that's why I like to write about it.''

'Red' is released on October 22.