CA was under the influence of some kind of meds, as stated by attorney Mark Nejames.
http://blogs.orlandosentinel.com/entertainment_tv_tvblog/2008/11/when-mark-nejam.html
IMO possibly benzos, over the last 2 years, which could genuinely affect her ability to recall things when asked under oath at hearings like this. (or anywhere else)
Adverse effects of benzos:
http://web4health.info/it/bio-benzo-sideeffects.htm
Last paragraph could also explain why it's taken CA so long to adjust to reality.
But this is just a possibility and MOO.
The effect of meds on her memory would be random and not selective though. She only claims to have 'forgotten' information she does not want to discuss ( as in incriminating). It's an easy cop out.