Fordola had a conclusion. It just came in later patches and wasn't tied up with a nice little bow on it like many other story conclusions.
She was redeemed, albeit not absolved, and finally overcame her personal demon of starting down the path to self-forgiveness. The saying, "every ending is a new beginning" has relevance here albeit with a twist to its usual meaning.
Her main purpose, however, wasn't her own story arc which is why they didn't bother to tie it up nicely. It was to provide the main foil for Lyse and to make Lyse question herself and her beliefs when they sometimes matched. They both came from similar pasts, but ended up on opposite sides of almost everything but had striking similarities that Lyse couldn't help but recognize in herself.
To compare: Yotsuyu had two conclusions, one in the original story and one in the later patches. Both of hers had a neat little bow on them, but SE just chose to unwrap Yotsuyu's tidy package one more time and give it a new, darker bow to wrap it up with. She was a foil to Lyse in some ways, but her purpose was more as the main villain for the expansion that is also self-contained to that expansion. Hence the neat little bows.