Sound devices

     Lithium, don't wanna lock me up inside

     Lithium, don't wanna forget how it feels without

     Lithium, I wanna stay in love with my sorrow
     
     Then again at the end:
      Lithium, don't wanna lock me up inside
      Lithium, don't wanna forget how it feels without
      Lithium, stay in love with my sorrow
     

      These highlighted words are repetition to show that the lithium or the "sadness in her life" is heavy on her mind. She feels that she can't escape from the loneliness/sadness.

       Darling, I forgive you after all.
       Anything is better than to be alone.
       And in the end I guess I had to fall

    

      The highlighted words are apart of the rhyme scheme.