(Getty Images)

It's hard to keep track of these two, one minute they seem like BFF's then suddenly they're enemies all over again.

It's official that Rihanna did they ultimate celebrity goodbye by unfollowing Brown on Twitter last night. Why? There is quite a few reasons we could throw around but it seems it was ultimately due to a rap Chris released online last Wednesday.

The rap is a freestyle version of Kanye West's "Way Too Cold, where the lyrics are directly about a certain ex girl friend of which is allegedly Rihanna. 

"Don't f--k with my old bitch/It's like a bad fur/Every industry n---a done had her/Shook the tree like a pumpkin just to smash her/Bitch is breaking codes, but I'm the password."

Unsurprisingly soon after Rihanna discovered the song she unfollowed him. Click here to listen to the rap.