When your venture was 0 months old, it needed a CEO to get it funding. Even if he played golf the whole time and lent only his name to the venture while you beat the streets to scare that funding up, he delivered on his job.
A CEO's job for a startup is not to be CMO or COO. It's to scare up money, and that money done got scared up. And now you want to move the goalposts.
Even if he's still out playing golf and you're still putting in 20-hour days, that doesn't mean a 50/50 split is unfair. It's what you agreed to, on the off chance you'd be anywhere near as successful as you are today.
Hate the game if you must, but your failure to understand the game has probably put you on the outs with your cofounder, and that has destroyed a lot of the value in the company, both yours and his. The whole purpose of a 50/50 split is to avoid this petty squabbling.
The correct advice is thus: Quit rocking the boat, roll back your hours to 8 or less (the company is not "yours" and never was), limp toward your first half-decent exit (either the company itself or just you), and focus on a new solo startup where you can be the CEO and CTO.