You put yourself in a position to be bilked, and you got bilked. You need to not work on "handshake commitments" or "no commitments". On a personal level, I fi

You put yourself in a position to be bilked, and you got bilked. You need to not work on "handshake commitments" or "no commitments". On a personal level, I find that simply accepting that people will hurt you, and deciding whether or not being an open, trusting person is worth the harm that might occur (I happen to think it is). Limit the amount and degree of 'credit' you give people to what you can equanimously accept as a loss, expect people to occasionally violate that trust, plan for it, and understand that it is simply one of the costs of being a decent human being. I never loan a book, I only give them away. If people later give them back, that's wonderful but not required. I don't ever let someone borrow something I wouldn't give them as a gift on the spot. In business, you either have full control, a negotiated agreement (which should cover things like how to make decisions when you disagree), or you're just a passenger along for the ride.