wtf??? client stuck on 8.1%, cant play game. this always happens with game clients, im so fuking sick of this. can u please fix this asap??? quickly admins please!!!

Luckily most games can be played without the Galaxy client.

how do i launch withcher 3 without it? every time i click the game icon it updates galaxy

A game installed through Galaxy will have a Galaxy launching icon. Navigate to the game's installation folder and manually create a shortcut to the game's executable, which does mean Galaxy features will not be available when you run the game.
From what I recall, The Witcher 3 has the executable in the bin folder of the game's installation folder. Just run that (or create a shortcut) and you should be fine.

JMich gave you a better answer than I could have :-)