I'm sorry for your loss. None of us ever believes this will happen to us, then it happens and any pregnancy afterwards you think you will lose it.

I was extremely careful with what I ate during my short lived recent pregnancy & I still lost it. The main cheeses you should avoid are brie, camembert & blue vein so if it wasn't one of those it is unlikely to caused a m/c. Also unless you were also very sick with it (running to the loo & throwing up) it wouldn't have been listeria that caused it, and that's the reason they say not to eat it.

Unfortunately in most cases you will never know what caused it. Most women go on to have a healthy pregnancy after such a loss. It doesn't matter how far along you were with the pregnancy it seems that most of us take it in the same way. We had already formulated plans for that little person.... even with a really early loss (like the ones I've suffered) a woman can suffer a huge amount of grief. It does get easier in time but it can come back and bite you when you least expect it. I found posting my innermost thought here helped immensely, I'm sure you will too.