Re: Not going well need advise.
As to a course of action, pretty much the only thing that would render your hive unfit for re-use, would be AFB. However the huge majority of these type of hive deaths are not AFB and in that case you could re stock your equipment with new bees with confidence.
There are some very balanced and extremely high quality posts in this thread there is most of the information you want. Some people would say you should treat the combs for nosema, and other such things, but apart from AFB, if you start in spring with healthy bees, they should be able to handle pretty much any residual infection of whatever, that might be left in the comb.
Just in case the hive did die of AFB, you can google some pics of AFB scale, and see if your hive has that. But if there is no dead brood in the hive, it did not die of AFB, as AFB kills the hive by killing the brood, by definition there must be some dead brood left behind as the last few bees are too weak to clean it out.
You can keep bees in the same area, not all hive deaths are caused by neonics. Fact is, neonics is the verified cause of death in extremely few hive deaths, and hives used to die before there were neonics. What is a much more common part of the picture, is varroa mites. They weaken the bees, vector all sorts of diseases, and even if the hive died of something that was not mites, in a very large number of cases mites were an aggravating or causative factor. My advice is put new bees in, and keep mite levels low, especially in the lead up to winter.
"Thinking Inside The Box"