I had an individual skills session last week and I'm still thinking about it today. The topic was learning to say no and not do anything I don't want to. In theory that seems pretty easy, but this is absolutely impossible to me. I'm so deeply convinced that when asked to do something I have to obey, because if I don't something bad will happen. Either violence will be used to force me to do the task, or someone else will be hurt, but in no case can it not have any consequences.

T tried to make me realize that this is absolute nonsense, that a lot of my thinking is really twisted but it didn't work. In all her examples I could see why she would think her way, but I kept seeing loopholes that validated my vision of things. Like one example was: what if T asked me to befriend an elderly woman and then steal from her.
All I could see was that this was stupid as T wouldn't ask me to do that, and if someone else did I better obey that person to protect myself.

Even with small things I just can't risk my "no" not being respected. Haven't told T this as I didn't remember it during session, but once my friend was saddling my horse to ride him and was using a saddle pad I didn't like (not enough cushioning). My friend thought it would be funny to ignore me and triggered a full fledge crisis with an argument that lasted a couple days because I was convinced that by ignoring my "no" he gave my brother the right to abuse me...

So how can I possibly learn to say no if my thinking is so messed up?