Imac severely infected

I have a 2013 iMac running OSX 10.9.4 that that has a root virus that can't be removed. I have formatted the hard drive no less than a dozen times as well as the Apple store formatting the hard drive. The file is in the MBR but in the form of a fat 32 file which technically shouldn't exist because Mac doesn't run off the fat system. When I look at the hard drive through my disk utility I see my mbr which is listed as partition 0 but my primary partition is listed as partition number 2 meaning theres a hidden partition. I saw the partition once and its an EFI partition which again isn't supposed to be on my hard drive. The partition size is only readable you can't write to it and its 290 mgs. I only saw it the one time and it flashed on the screen for a split second. When I format the hard driver that partition is skipped over so whenever I install the OS the malware/virus loads along with it. It uses a package sniffer which I assumes allows the hackers into my system. They have locked my key chain which is where all the passwords and certificates are stored they have disabled me from getting into my system preferences to make any changes to my security settings the only way to gain access to these files is to format my hard driver and I have an ipv6 ip address listed in my network folder but yet I have the ipv6 disabled through the software settings in the software of my router settings. 

I have had every email account I own compromise and all my email deleted. I closed my Facebook account 3 times in a week only to have it reopened by the hackers. I have seen a short cut on my safari bookmarks that has allowed me to go directly to my FB page and log in anonymously without a password. They have stolen money out of my checking account which has brought the police into investigate but this has yet to deter the hackers. Even now as I write this Im sure they can see or will be able to see my post beings everything is loaded into 2 different cache files in my library which is uploaded into their system. I know they use the server Jalisco which is based in Mexico someplace. I have seen the code they used to get my passwords off my system and how they allow themselves to be the administrator.

As you can see I am in a dire situation and desperately need help. I tried to load a png that shows where the password can be extracted but it won't upload since its nt a txt file