Most Helpful Guy
My advice is that you should split the house proportionally with reference to how much each of you originally paid.
One of my preferences would be to sell the house. So if you contributed 50% to the purchase price of $200,000 (in other words you contributed $100,000) and the house sells for $400,000, you should get $200,000.
Another way would be for you to sell your interest in the house to him or for him to sell his interest in the house to you, though you should still get an independent valuation to see how much the house is worth. Again, you get 50% of the current value of the house, if you paid 50% originally.
Another option (though not my preference) is to continue co-owning the house. Either you live together but with separate lives. Or one or both of you move out, and you rent part/all of the house out, again working out your shares of the rental income based on proportions.
It really is best to work this out without accumulating legal fees. If you can get everything or pretty much everything you want without restorting to litigation, I recommend you do that.