Preggo, I would be careful about diagnosing your husband in his current state- he's in the fog of an affair, and even the most level headed person acts insanely in the fog.
BPD is something you would have felt in your relationship from the off. BPDs have a very hard time with real relationships because they don't feel emotion the way most of us do. They tend toward risky, unhealthy, behavior, feel that the world revolves around their issues, and generally leave a trail of strained relationships and broken promises behind them. Is this how you've always known your husband to be?
Don't distract yourself with diagnosing your husband. Work on changing yourself back into the woman that he thought he was marrying. Keep yourself focused.
