Some answers

When did I  realize I  had alters?
2006
Why didn't I know?
Everything jived ... everyone forgets things or doesn't remember what they said or did. I had lots going on in my world that was trauma in ways I clearly remember.  Like having my fingers crushed together so I would pay attention or comply...or just for the fun of me squirming. I remember being kissed inappropriately by family members. ..almost photographicly clear. I was married for 11 years. ..I didn't know. But looking back some big signs were there like severe "panic attacks " that mimic seizure like symptoms. I don't remember some things done in anger that he swore I  did but I  don't recall.
Anyway...next..
How old when sexual abuse occurred?
Incidents different in nature from (best guess) 4- 13.
Do I  hear voices?
No. The alters have some communication between them...particularly the younger 2 who took the majority of abuse incidents. I have a noise in my head that comes and goes that is like being outside a closed loud and busy auditorium. I also recently started to hear a baby crying. No voices. More a feeling.

Ok....I am done for today. This is harder than I ever thought. ..
Maybe it will help me and my best hope is someone else.