I always felt like it was about Kim.
If she sees him again (she=Stevie. him=Kim)
Will your very best friend (very best friend = Robin)
Will your very best friend
Have been replaced by some other?
(Kim went away after he and Stevie split. When Stevie ever sees him again, will he have found somebody new, and then Robin will be really gone, replaced by some new woman?)
And the dream says 'I want you'
And the dream is gone
(this bit kind of reminds me of how she says she felt Robin in the house, the baby's cradle would always be rocking but then one day she went into the baby's room and the cradle was no longer rocking and she knew Robin had finally gone and it was wrong for her to have married Kim. The dream is gone=the cradle is no longer rocking=the marriage is wrong)
Of course it could all be some book she was reading. Or soap she was watching. Or the drugs talking.
Whoever said Lindsey saves it, I agree.