Col. Quaritch had a tough life. A proud military man, he found himself playing mercenary boss-hog on the most inhospitable shithole in the universe, a planet that emasculated him on his first day by nearly clawing his face off. Humbled, disfigured and alone, his life became a thankless grind in servitude to a corporate shrimp-dick and a bunch of hippy-dippy scientists who wouldn't know survival of the fittest if it came and gnawed their nuts off with its 'Oh-so-pwetty' glow-in-the-dark teeth.
But then, one day, a ray of light entered his life. An ex-marine, drafted in to replace his hippy scientist brother. He wasn't too bright and had a constant look on his face like a monkey jerking off for the first time, but he was wheelchair-bound, which reminded Quaritch of his own broken state. Sensing that he didn't fit in with the scientists, Quaritch reached out to him and discovered that they shared a love of service and action. He wasn't like the others; this young marine was cut from the very same cloth as he. They immediately recognized each other as soulmates.
This wasn't an easy realization for Quaritch, who had become used to being misunderstood, but slowly and surely he let the young man in and a bond was quickly formed. Suddenly, Quaritch had found himself doing something he had not brought himself to doing in many years; giving. He offered the young marine a chance to get his legs back if he helped him trick the hippy scientists and find a way to clear out the planet's religious extremist Thundercat population. Sully agreed, giving Quaritch a thrill of the kind he thought he would never have again; the thrill of kinship, of connection. He and Sully would kick the Thundercats' asses, grab all of that stupid mineral nobody had even bothered to name properly, and abandon this rock for a life of adventure together. He felt respected, he felt needed; dammit, he felt loved.
And then Monkey Boy went and stuck it in some blue poon, and everything went to shit. Rejection like that'd make you want to stomp someone with a mech suit, too.