I'm in a center lane getting ready to make a left turn across 2 lanes into a parking lot. A van with another car behind it in left lane of oncoming traffic begins to make a U turn so I proceed tomake a left turn. The car abruptly changes lanes to go around the van and runs into me. Am I at fault for failure to yield when the other car made a change of lanes from left to right to pass the van?

Yes, I was a police officer previously in life. I have wrote many tickets and studied traffic law for the state of GA.
It can depend on even the exact wording of the law itself, since to make the case, they have to provide or prove any required element of the law.

Since there was two cars coming, you had to turn in a manner that would clear any on coming traffic the other car has the right of way to go straight ahead.

You best chance, show up, and hope the police officer who wrote the ticket does not show up, and get case dismissed

You were aware of the car behind the van, right? You saw the van making a turn but had no idea what the car behind him would do. Therefore you should have waited to determine what that car would before making your turn.