As to the original question.
I think I'd look at the ingredients If the chocolate contains fats other than cocoa butter. It might contain more harmful saturated fats rather than the stearic acid in cocoa butter which doesn't increase LDL. It could possibly include partially hydrogenated fats ( trans fats.)
As to abstaining from it because we're diabetic, why? You might be doing yourself some good!
Lots of studies have suggested health benefits of small amounts of dark chocolate. It's been linked to serotinin release which makes you feel good; depression is common with diabetes . It may lower blood pressure. Some studies have shown it to improve blood flow. One study even suggested it increased insulin sensitivity. The most recent shows a benefit for people with liver disease. I also know of an ongoing study into CVD prevention where one group is eating a prescribed couple of squares of dark chocolate a day.
Sounds good, and a quick Google will probably find more possible health benefits. (To be honest, the studies aren't that brilliant as it is difficult to isolate one element of the diet but there are certainly a number of possible positives
)
The biggest drawback is that all choc is relatively high in calories so a lot of it might put on weight. Luckily, most people can't eat huge amounts of dark chocolate.
If dark choc makes someone feel good, isn’t going to cause an obvious problem and they are not eating huge amounts of it why on earth not?
Quality if life is important.