Wow, you sound like you certainly do love your wife to hang on and be be put through so much. I am bipolar too and understand this type of behavior.
#1-Has your wife been back to seeing her psychiatrist for an evaluation? She sounds like she is needing a medication adjustment. Is she compliant with her medications or even on them at this time?
#2 I have learned that when in a relationship, nobody should talk that rude or be that inconsiderate with you, bipolar or not! You need to step up to the plate and let your wife know that you will no longer tolerate that type of talk from her. You don't deserve that. You should then walk away after telling her, that when she calms down, she can approach again. But you have to let her know that it will be no longer acceptable from you.
Is your wife trying to work on her bipolar issues? You sound like you would be a wonderful support to her if she would just try to cooperate. Have you or her considered going to a therapist? Most people who have bipolar incorporate the help of a therapist as part of their wellness plan. This can help her to find ways to get use to dealing with her emotions in a new and healthy way. Perhaps you could offer to go with her from time to time to help you understand what she is going through. You may want to get the help of a therapist for your own self as well if needed.
These are just some of my thoughts. I'm sure others will be along to give you some of their suggestions. There are a few people on the board who are also in relationships with bipolars that also come here for support.
Keep us posted.