Sunflower, from what you have shared it really sounds like both of you are struggling with the after affects of narcissistic abuse. I honestly feel that both of you should spend time in therapy with a trauma therapist as you have mentioned struggling with flashbacks and how you struggle to sleep and distance.

I am going to provide an article for you to read, please do so with caution because you may identify with what you read. From what you share it sounds like both you and your boyfriend struggle with shame too.

11 Signs You're the Victim of Narcissistic Abuse

The right therapy can help both of you heal and learn how to get closer as it sounds like you both want to "care and love" each other but struggle with fear that was created from the toxic/abusive partners you both experienced in your past when you both were much too young to really understand and better protect yourselves.