manyinsiders, I am so sorry that your first experience of this forum was to be told that the way you think of yourself is "wrong". It saddens me that you have taken that to heart so. A support forum is supposed to be one of support, not dictatorship. You are not "wrong", you are you. (Plural.)
There is nothing wrong with your use of the term polyfragmentation. It was and is an adjective in much the same way that "coconscious" can be used to describe a system. On another forum there are posters that have had their therapists describe their systems as "polyfragmented". Again - it is an adjective. It never was a diagnostic term and it doesn't have to be for you to use it as you do. No, it isn't a diagnostic term (it never was, and was never used as such), but it conveys information and it is OKAY to use it.
Even if some people don't like it or wish you wouldn't.