Dear Tim. Indeed adoption and any form of abandonment is the cause of CPTSD, I think you will find this helpful https://cptsdfoundation.org/2021/12/08/adoption-disconnection-reasoning-cptsd/

The aloneness and abandonment and loss of worth is very real. Please look into NARM therapy, it iss the most affective at bringing recovery to these early attachment traumas.

Sending love to you and all your parts :)

Gemini