Start another grow spot on your own. Take care of both spots the best you can. Growing weed isn't that hard, and its not even June yet, why is it soooo much work? Once they're planted, it should only be a couple hours of work/week tops. Just wait until he makes you trim it all, then you're really going to be upset with half.
Also selling it is a job in itself. You really made a bad deal if you agreed to sell it all and give him half the money. He should get half the money at a bulk rate. If you guys get a pound, he should get $ for half of what a pound is worth. Not the amount after the pound is sold for, after breaking up into smaller amounts, and making more than you would by selling a full pound. If you really have to split all money made, you should just sell it all at once, in bulk.