Not every low carber sees their total cholesterol drop. There are a few issues with that and some of them have to do with the test used. It is designed for people eating carbs and having rather high triglycerides. When triglycerides fall, which is a good thing, the LDL looks like it goes high, but it doesn't really.

Lots of articles and such in the thread linked in my signature.

Jimmy Moore has a new book out on Cholesterol. I haven't read it, but it might be a good place to start. Gary Taubes, William Davis (cardiologist), have written books that are good places to start educating yourself, and your wife, on why fat is not the culprit for heart disease, carbs are.

I think of them all, I'd recommend "Wheat Belly" the most.