Are you completely convinced that he's cutting you out? Is there ANY chance that he's telling his buddies "It's weird, the knows I'm doing this deal for us and for some reason he hasn't contributed"???
A long shot maybe but peoples personal perceptions can be skewed by circumstance and flawed recollection.
Or is this kind of deal one that you would have a had to sign your name on by now were you to reap any rewards?
In the end your best bet is to take me on as your new partner, it's the only logical move.