Sorry to hear you have been going through so much. Part of this might be your wife's ownfrustration with her uc. The other part could likely be from the prednisone she is on. How high a dose is she on? The higher the dose the more likely the side effect.
From the general precautions for prednisone:
"Psychic derangements may appear when corticosteroids are used, ranging from euphoria, insomnia, mood swings, personality changes, and severe depression, to frank psychotic manifestations. Also, existing emotional instability or psychotic tendencies may be aggravated by corticosteroids."
Source:
http://dailymed.nlm.nih.gov/dailymed/lookup.cfm?setid=78fb9762-c2b2-4e32-ac4c-e95cba11198e