mileage may vary, and unfortunately nobody can answer this question for you with absolute certainty. I think for most, though, the suffering is at least reduced over time. I don't know what your situation is, but I can share my own experience and perspective.
I was abused, controlled and manipulated for the majority of my life. two separate people who, very similarly, systematically destroyed everything from my sense of self worth to my very perception of reality.
after escaping person #2, it didn't get any better for a very long time. several years of relentless nightmares, paranoia, anxiety, and bringing myself to a pathetic, drunken stupor every single day just to try and escape it all. it didn't work, but oblivion was better than dealing with the reality of the situation at the time. Still, it consumed my life, it tainted my every thought.
I'd guess it's been maybe about 6 years now, since the beginning of the post-abuse nightmare. Things have gotten at least more tolerable. I still look over my shoulder, I still flinch and panic at slight (and false) indications that I may have done something wrong, once in a while a nightmare will come and fuck up my night. It still revives the horror to receive a letter in the mail from person #1, for a little while. But it isn't as bad anymore, the thoughts aren't as extreme or obsessive. It's more like unresolved background noise now. I'm still very damaged and have a difficult time navigating interpersonal relationships. I still deal with occasional guilt and doubt. But there is less suffering than before, it doesn't consume every facet of my existence. It's more of a concrete fact in my head that I was abused, rather than worrying that it may have been the other way around, as my abusers would have me believe.
so, has it gone away? absolutely not. however, it doesn't all lord itself over my life the way it once did. I can only hope that the pain will continue to very slowly diminish over time.
Give it time, and go easy on yourself; 3 years can still be relatively fresh. I hope this helps, and I hope you will come to find some much-needed peace of mind and solace.