Chess

My wife has recently taken a liking to playing chess. We are very close in chess abilities: she is a morning person and she [naturally] wins when we play in the morning, I am an evening person and I win when we play in the evenings. Yesterday evening we were playing and I was winning, as the game progressed, she dug deeper and deeper into the "black" side of things. When I tried to abort/concede the game, she took a large jump to the dark side. I ended up engineering my own defeat while making it look like an honest win for her. By the end of the game, she was back to white. After reading this co/BPD stuff I realize that I have "enabled" her "emotional blackmail". But practically, what can I do? I'm trying to run interference for my son to create some peace in the house. This literal game is a wonderful metaphor for my life: I can't quit, I can't win -- if I do either, I hurt my son.