I was just wondering if the flash backs ( or in this case, reliving "It" every single time I try to lie down and rest) EVER ease up or go away?

Also was wondering does anyone else struggle to be sociable etc. I got invited to dinner with friends just at her apartment four adults total and one kid and had to ask WHO exactly will be there etc, can't handle surprises. Is that just part of PTSD or anxiety disorder? Just wondering, ty for listening.