HI dass
Welcome to PC!
In regards to your query:
You don't know. Until you know. What I mean is each person and each part figures it out, describes it, and comes to accept it in their own way and own time. Then once you accept it. Then it almost like you always knew.
How most get diagnosed?..Trial and error diagnoses medications and treatments and nothing fully fits or works then something shifts changes grows becomes presents either in front of therapist or Dr..or reported or sometimes recorded (don't wanna talk about it!)
Sorry sidetracked anyways..we've already been dxd with everything else under the sun and been on almost every med ever made and been in treatment since childhood..everything else ruled out or incomplete all other explanations exhausted. Most do not get dxd with DID until pretty much it's the only dx left in the book! *lol*..at least that's what the process of diagnosis was kinda like for us..
Hope you find your time here at PC to be helpful and coforting
Be Well and Keep Writing!
-LITW