WTF no just no mikasa was going to kill her and they were never friends only rivals.

MIKASA PRESPECTIVE

Their relationship is implied to be some sort of rivalry. Their animosity deepens when Annie was found to be the Female Titan, and was responsible for the deaths of countless soldiers and Eren's attempted kidnapping. Things came to a peak as Mikasa became fed up with Annie's games and called her out as the Female Titan that had attacked them. With that exposed, Mikasa stopped Annie from escaping by cutting off her fingers and forcing her to fall off of the Wall.

ANNIE PRESPECTIVE 

Their interactions suggest some level of rivalry, with Annie once describing Mikasa as a "beast". This only worsens when Annie's true identity is revealed, with Mikasa aggressively confronting her and later aiding in Annie's defeat.

In other words they fucking hate each other and how the fuck do you think two people who almost killed each other  become a fucking couple this ship along with Ereri, Jean x Eren and some other ships are fucked  up and unexplainable. 

COMMENT!!!!!!!!!!!!

I challenge whoever wants to start a drama then do it ,I have bullets waiting for them