Belle Prater's Boy doesn't end with Woodrow finally being reunited with his mother. In fact, at the very end, it's been a year since she left and he's still no closer to finding out where she went. He's even lost hope of hearing from her again because he realizes that she's started a whole new life somewhere, one that doesn't include her old family:
It was a moment, I reckon, when we both faced the truth. Aunt Belle had left Woodrow on purpose just like my daddy left me. Not because they didn't love us. They did. But their pain was bigger than their love.
You had to forgive them for that. (23.34-35)
But even though Woodrow and Gypsy don't solve the mystery of Belle's disappearance, they still reach resolutions within themselves. They both come to forgive their parents for leaving them—Gypsy because she understands why her father killed himself, and Woodrow because he sees that his mother was so miserable in her life and she had to get out.
In the end, Gypsy and Woodrow are finally able to see that their parents didn't abandon them because of a lack of love—they left because they were in too much pain. And with this knowledge, Gypsy and Woodrow are ready to forgive them and move on with their lives.