I was thinking about this recently in the context of the game Diplomacy. One way top play is to model your opponents as rational self interested actors making the optimal move for them at a particular time. This can seperate off your attitudes to people in the game from your normal emotional reactions (e.g. move from "he stabbed me in the back" to "He acted in his self interest as I should have expected").

[An interesting exercise would be to write down each turn what you predict the other players will do and compare that to their actions.]