Can i ask a question ? Why would you repeatedly talk about your ex to other people constantly if she did you wrong and it was a long time it happen

She's just coming into my head a lot . I didn't think of her in ages up until about a 1 year ago and since then she's after coming back flooding into my mind ?
We ended bad , a few nasty things said on my behalf cause I knew she was cheating on me . I've nothing against her and I wish her the best but I can't understand why she's flooding into my mind again .
I can't seem to let her go out of my mind . Is it trauma or is it something else I just dont know.