HUMMER WONT CRANK..NEED HELP

[H2FAR]

Howdy

Hoping someone might have experienced similar and could give a little advise. A few months ago my 35000 mile H2 wouldn't crank with the key in the run position. All other electrical systems seem fine. A few hours later it worked just fine and no trouble for weeks. Then it became more frequent and by cycling the key several times rapidly I could get it to crank. When that little trick stopped working I had it towed to the dealership and they replaced the ignition switch. Second tow to dealer resulted in checking the connection to the fuse block, putting some dielectric grease on the connector($125.00). Third tow to dealer they turn the key and it starts...sorry. Fourth tow to dealer new starter. Fifth tow to dealer they discover that a dead cell in my battery is the culprit...I am told it is acting like a resistor and robbing the truck of power. Seems strange because everything in the truck lights up and works fine just no crank. Low and behold get home from dealer Friday and the truck has been dead in the driveway ever since. Whats left ? I hate the fact that this licensed GM dealer is throwing parts at it and making a fool out of me. Any help would be appreciated.