I know the song isn't about a pair of girls, but I decide that now: it's about two girls. Let's call them F and A just to make it easier. They have fought about a boy and doesn't talk to eachother.
The video starts in the morning.
You see one of the girls (F) lying in her bed and the alarm beeps. So she jumps out of bed and starts getting ready. In another part of town her friend (A) is doing the same procedure.F opens the refrigerator and you see lots of pictures of her and A.
A takes the keys and drives her vespa.

F is on the bus, it's still morning.
You see flashbacks from the time before the fight. 

You see flashbacks from the fight.
You see when F ignores A's calls. (When the song goes "You never returned that call") 
And in the end F stands at the platform and the trains are going past her and A steps out of one. Then F stops her and mimes with the lyrics "I don't mind, if you don't mind. 'Cause I don't shine, if you don't shine".
You see flashbacks from the time before the fight. 

You see flashbacks from the fight.
You see when F ignores A's calls. (When the song goes "You never returned that call") 
And in the end F stands at the platform and the trains are going past her and A steps out of one. Then F stops her and mimes with the lyrics "I don't mind, if you don't mind. 'Cause I don't shine, if you don't shine".
And the message is: