Of course milk chocolate can be frozen - haven't you seen in the supermarket freezer the ice cream version of Mars Bars or any modern choc-ice (they used to be coated with a "chocolate FLAVOUR coating", but now that's only on the really cheap ones, they've found a way to do it with real chocolate)? Chocolate will keep forever anyway without freezing. The high sugar content means that bacteria cannot live on it. I suppose the oils might oxidise after a long time, but as long as the chocolate is in an air-tight wrap, that wouldn't happen.