This is very true. It is so hard to hear or trust your inner voice after abuse. It takes a lot of hard work. This blog is one of the ways I have been able to explore my thoughts. I cannot recommend writing more as an aid.
It takes practice and patience to learn to hear your own intuition and inner voice, after you have been conditioned over time to ignore yourself.
But you have a wisdom inside of you that is compassionate and intelligent. The narcissist tried to silence it, minimize it, confuse it and discredit it. But you still have an inner voice that can lead you in the right direction for you.
Feel your senses and what they are telling you. Every sensation is part of your guidance system. If something feels wrong, it probably is.
You can override the brainwashing by a narcissist. Learn to trust your intuition and guiding voice.