I hate to tell you this because I don't want it to send you spiraling but they don't go away BUT I can say there are plenty of resources available to help you manage them better. I spent 18 of my life thinking that if I just did more, became more perfect then I would be free from the pain of my flashbacks and dissociative state but that's not how it works. I think It's really important that you have self compassion and set reachable goals for yourself. The process of somewhat rewiring your brain isn't an easy task. Right now, I'm reading a book entitled Complex PTSD: From Surviving to Thriving by Pete Walker and It's helping me immensely. Now that's not to say I'm not struggling. I can't sleep. I have terrible body horror, gore nightmares. I cry all the time and I'm really kind crawling in my own skin right now but instead of fighting the flashbacks, shame, and pain I'm accepting it. Once I did that it seemed like I could finally start to grieve in little spurts. Also, I finally see myself as someone who survived monstorous, life threatening abuse instead of viewing myself as a defect so much. That has given me a little bit of my humanity back. Even to get a tiny bit back brings so much peace.
As far counseling goes, I don't where you're at with that. I know personally that I'm not emotionally ready right now because I distrust people so so much. Right now, I'm educating myself on trauma, making sure I take care of myself emotionally and physically as best as I can, and finding this community here has me finally talking about what happened and just talking to other people again which has been so therapeutic. I know I need therapy but I'm going to ease into it and that's okay. Sometimes, you have to treat yourself as another person. Would you be so hard on someone else experiencing the same difficulties? My guess is you wouldn't? I hope that helps some. Don't be afraid of talking here because this is a nice place.