Guilt

Through performing my scene it gradually became apparent I me that lopakhin is driven heavily from guilt and his need to avoid it and supress it.

Weather it's his guilt of buying the orchard or from the guilt he has of what his ancestors went through, he is continually doing his best to of load it. I also think he is in denial about his guilt this is shown through his constant need to vocalise to the other characters his child hood. This is almost like a self reassurance that he is a good man. 

He deals with his self made guilt of buying the orchard by telling himself it's Ranyevskya's fault for not listening to him.