Just throwing this out there for consideration:

Not all of our emotions come randomly from mental illness. If your fiance acts like a sore winner, it makes sense that you would feel agitated by that. But your automatic response of blaming yourself or your mental illness, makes me suspect that if you asked him to not act that way, he would dig at you for being "too sensitive". Do you think that would be the case?

All I'm saying is that if someone is acting like an immature little douche, it's not the BP that's making your irritated, those are just normal feelings.