It's real for sure. And if you think about it, you can understand why it happens.
With little kids, they don't have a formed personality until about age 6. As things happen to them, the child handles it and slowly those actions and emotions become the child's personality. When the child is traumatized before the personality is formed, the memory not only tucks the trauma away deep in the brain, it tucks it away with the part of the personality that is unformed. The brain is trying to find a way to handle what happened and it does so by putting everything away for another time and day.
Then as you grow up, you develop post traumatic stress disorder. One of the hallmarks of PTSD is flashbacks. Only it seems in those with very young trauma where the personality is tucked away, when we have a flashback, not only does the memory come back, it comes back along with the personality that got tucked away. We become the age we were hurt. When the flashback is over and we are coming back down to earth, it goes away and we become ourselves again. Your brain is telling you that the "other time and day" to handle the trauma is here.
What I have done that has been successful is learn first how to survive and thrive despite the switching. It can be done and maybe you should look into something like DBT treatment to get that part done. DBT gives you tons of tools to help with everyday life. Once you have that part down, then you can go after why it happened in the first place.
Try to find a therapist who specializes in PTSD treatment as that is the cause...traumas. They can help you get into DBT and explain more about it. They also do therapy along with DBT and you start to learn why and how it happened.
If you go all the way with treatment you end up integrating those personalities into your own personality and life. That is what I am doing now. It's hard...very very hard.
But most learn how to live a good life despite DID. I know many who are doing it. You aren't crazy...you are a victim of trauma at a very young age and that is how the brain survives. DID is now seen as the worst case scenario for PTSD but then again, it is also the most creative way the brain can make us survivors. The mind finds a way.
Please find a way to see someone who does work with PTSD survivors. You can make this work.
Hugs from all of us................Jenny