It definatly went out again on its own, or atleast seems that way to me and there is no possibility that someone else did it, I'm secure and no one in my home has any idea about BTC.
Physical security does not matter as much when it comes to digital things like Bitcoin. If the address that the Bitcoin is being sent to without you doing anything, then that means that someone else has somehow gotten your private keys. This means that you may have a virus on your computer, or the random number generator was bad. Either way, you no longer have control of the Bitcoin.
Are any of the address receiving the Bitcoin addresses that you intended to send Bitcoin to?