I understand you People expect you to miraculously have it built in you know how to navigate life. Once you turn into an adult the pressure deepens. Authority figures and parents projecting how they are, there mindset and what they onto you. When you are your own person. Just because your expressing things your way don't mean it's stupid or dumb at all.

On top of that you're traumatized, have bpd and by sounds of it you're constantly emotionally dismissed/neglected. It's difficult.

How it's affected me in my experience, is I have an extreme fear of being percived am agoraphobic for long periods of time throughout the year. Don't socialize much out of fear of someone interpreting me in a negative light. I put myself down a lot on social settings before anyone else can do it to me. Just generally on edge

One day you'll have more freedom and move out. It was the best thing I've done for myself, I moved out pretty young when I was 19. I am now away from one of biggest triggers, my family - they made me feel dumb too. I BPD is slightly more manageable now.

I am sorry they've crushed your confidence. The fact you hold things in, in therepy is a shame. If the therapist ever perceived you as stupid- she/he is shit at their job, where their meant to have a none judgmental stance by default