Hi justneedtotalk! Irritability, frustration, and related anger associated with bipolar disorder is not uncommon, but many do not direct it at those they love. That's not to say that people can easily tolerate it even if it isn't, but when it is, it does qualify as a form of abuse. Either way, it is a person's (your spouse's) responsibility to work on treating and preventing such behavior. Just saying they have bipolar disorder (or some other disorder) is not enough. It seems to me that it is high time that she start doing the apologizing, not you, or at least acknowledging that her disorder (or behavior otherwise) is out of control. That means, in my book, that she start trying to rectify the behavior or at least minimize it. Medication change? Medication again (if she's quit)? Therapy? All of the above?
You married your spouse for her, not her disorder, and you have rights to expect her to try to work at being healthy and take responsibility, when appropriate.
If when stable, your spouse's expectations can not be met, you have the right to decide what your limits are. You have the right to set reasonable expectations for her, too. If she doesn't meet them or try in good faith, perhaps she's failed not as a result of a disorder, but as a spouse.