Pretty much an eulogy of sorts focused on The Gift and the whole Season Five as well as the 147 days when Buffy was gone from the living world, focusing on Dawn's grief and sadness, however being presented "sort of" from buffy's point of view..
Colored stuff is present (S6 premiere), gray stuff is either The Gift memories or even older memories of what they went through together.
Its as if Buffy, back at the tower, in The Gift, telling Dawn to not be sad, to accept her death and to be able to move on with life and Dawn at the same time remembering Buffy.
The Video covers the events of S5 and leads to the start of S6.
This song always associated for be with this exact situation.
Song: In Passing by Indica.