Hi pete, sorry you are suffering from the periodic episodes your wife is having. Under ideal circumstances the meds will stabilize the patients moods so they do not wildly go from one to the other. Talk to her psych doc and tell them she is not staying stable and her moods can be very angry and out of sorts. They may decide to change the meds. If they do nothing, and she continues to be unstable, another option is to get a second opinion from another psych doc.

What is important is to take care of yourself. Being a caregiver can wear you down and cause you to feel depressed or anxious. Some caregivers even find it helps to enter therapy to deal with the flash back and to deal with one's own challenges so as to be more sensitive and responsive to the moods of their spouse. Ridding one's own anger and nasty responses along with getting the right mixture of meds can help reduce the patients eratic emotions.

Here are several articles on how to cope with a bipolar partner.
Psych Central - Search results for Coping with bipolar partner