Looks to me like she would rather keep Obama in the White House, than a Republican, even if he is her own husband.
What it tells me is that you don't know what you are talking about. She has made appearances with Cain. She was at a fundraiser I attended - look at my profile. That was at the Lenox Grill north of Atlanta. She spoke a bit there and she is VERY supportive of Mr. Cain, and I know for a fact she is also a social conservative.
She was at his announcement rally also. See picture below:
She also supported his 2004 Senate run:
