How is diaper fetishism related to depression particularly depression associated with major childhood trauma and feelings of abandonment?

The adult world does not allow this "dependence." Yet, many crave it, want it, desire to be young and innocent and safe. They don't have to do anything, but mind "mommy" or "daddy" and they will be okay.

We all want to be loved. To be cared for. To be safe. Unfortunately, abuse and neglect takes this sense of safety away from some. It's not hard to conceive that a child's mind would imagine being an innocent, cute, little baby that will be loved regardless as an alternative to a reality where they are not loved or protected or safe. I'm not sure why this gets sexualized, but it doesn't really matter; sexual satisfaction is not the main course for the adult baby. It's being in the role, being safe, being controlled so that no decisions have to be made, other than to suck on a bottle or a pacifier. It is safety. It is being loved. It is being accepted unconditionally.

Who wouldn't want that?

Any person who had been abused or neglected will have their demons to conquer. Depression is a side effect of holding in one's own emotions. People who have been abused or neglected have learned that it is not safe to reveal their feelings, so they hide them inside -- even from themselves! Unfortunately, our creator made us to be feeling beings, and this loss of emotionally connectivity with our minds can easily lead to depression.

It seems to me that being an Adult Baby is part of the solution of recapturing one's inner heart, and that depression is the result of NOT doing so.