He may be happiest being left alone and not fussed over. Part of his issue may be that he doesn't get turnout with other horses. Being kept isolated can have serious negative side effects on a horse's mental well-being.
That being said, some horses just truly don't enjoy being messed with. My Dad's horse is that way, he despises being groomed or petted, he would much rather you take him out to work and then leave him be the rest of the time. Since he is such a high power/high drive animal, he may benefit from more work.
As for the whole 'emotionally unavailable' thing...horses just aren't built like that. They don't need friends, they need leaders that they can follow and have respect for. Someone that they will have confidence in. In every single horse I ride, a good working partnership is of primary importance followed distantly by an emotional bond. I can have the partnership without the bond and get along great, we just do the job and that's it. However, a bond without a good working partnership is pointless.
Get him working well for you, earn his respect. After that, the bond may or may not come but it will certainly not come before you have his respect.