I totally can relate to that. My parents, siblings, friends and even my psychologist always claim the same shit. Let the past behind you, time heals everything, move on with live. Like I get what they're saying and there's some truth behind it. But it's just extremely painfull nonetheless. Also time doesn't heal "everything". As you said there will almost always remain scars. However how big those scars are vary.
You sound like yours aren't easy to treat at all. Mine neither. Like I know I can't change my past and it's also true that I need to move on. For some people it basically means either move on or die. Atleast for me that's the cold reality. And I know that. But those phrases are so hard to swallow especially if the person quoting this has not experienced real trauma.
My parents have a calendar with family pictures on there. On the current photo page from last year are photos from them celebrating christmas. Without my presence. They all look so happy. Everytime I see it I ask myself. "Where were you on that day?" I can't exactly remember. But when I try to look back to that timeline I see mixed, blurred scenes and images of me having withdrawals, seizures, vomiting, selfharm, my ex-girlfriend, confusion, paranoia, psychosis, delusions, addictions, police, psychward, lonelyness, overdoses, ctb attempts etc. etc.
This has been going on for years. I have to live with the horrible consequences everyday. And I know I need to move on and improve my life or like I said die...but they say those phrases like it was nothing. And without real meaning. Cuz they just don't know...how fucked somebody can be. How deep down the rabbit hole actually goes. How much pain you have to endure everyday while they live a good live. It hurts even more.
I also decided to ctb months ago. But I'm still here like you. I'm running from myself everyday. Literally cuz I go jogging lol. And I try to improve so hard every fucking day. But I also tend to ctb. So I said to myself I'm gonna keep doing this till my meds are on the max dose possible. They're against my extreme perception disorder. My brain's just fucked. So I don't have a date said really but I keep moving on a little longer. But it sucks so much to be here. Seeing all the happy people. So painfull everyday.
Anyways I hope things may turn around for you and me for the better eventually. Maybe you can stick around a bit longer to see. But I know the phrase "things can only get better" sucks too and I respect any decision you might make.
Nonetheless I only wish you the best

Sending hugs.
Holy shit this text got long.
I'm also venting a bit just so you know haha