We shld understand that there is no scope for Kashmir to be a free state
We know that pigs can't fly but same doesn't stand for separatists. It's not that I don't know that it's impossible for Kashmir to exist geographically independent without India.
The wave of separatism in Kashmir isn't affiliated to any kind of nationalism (there is no real thing called Kashmiri nationalism at first place) but same form of ideology which was responsible for conversions of Persia, Egypt and Southeast Asia or creation of Al Qaeda, ISIS or Taliban and even the state of Pakistan itself. They may or may not subscribe to idea of Pakistan.
Unlike first category which will be funded only till Pakistan exists or fails to remain significant for world, second category will continue to be used as a faultline explored by India's enemies.
Both categories have a kind of support for each other now as India is their common enemy. If we leave that place (which won't ever happen), just be ready to watch another Syria or Iraq.