what wallet you use? blockchain? just now my BTC also lost...huhu..maybe can change to Xapo Wallet..its more secure
I'am pretty sure you didn't read the thread otherwise you would know it's Multibit .
@OP I'am sure about the hacking thing mate , otherwise why wouldn't he take all the BTC on your wallet , Are you sure no one on your family have access to your PC/wallet (if it has password) ?