It's a woman, with short bleeched blond hair, singing and dancing all alone, in a large dark room. She has 80s clothes (like funky workout attire), and the camera is following her as she dances. There are some tektonik moves in her dance.

She sings to a guy telling him what to say when he breaks up with his woman for her.
Like 'tell her you love me' or something, I don't remember the lyrics so well.

Maybe
"Won't you tell her that you love me
Tell her that you've changed you mind
Tell her that it's over
Tell her please she's out of time
Won't you tell her that you love me
Tell her that it's over
Tell her please she's out of time"

Song: Tell her
Singer Princessa

But she is not blond...

Call Your Girlfriend by Robyn :)