Thank Belier. I think you're right and that what I'm thinking of is only privacy but I'm treating it as secret out of desperation.
"We keep something secret because we believe the cost of telling is so high that it's virtually not a choice at all."
Usually, when I'm around other people, their moods and thoughts seep into me a little. With my mother it's much more difficult. She is ranting, raging, tearful meltdowns...
I sometimes have thought of getting tattoos to remind me who I am. Sometimes when I'm with my mother I think of tattoos I've imagined on my body and it helps me remember that I'm a separate person who doesn't need to get caught up in my mother's personality.
When I'm alone it's easy to separate others from myself. Which is why I want to live alone and not with others.
I don't trust other people to be different from my mother.