I am so sorry.
My mom deals with this at times with my nephews. I am so weary of the way my generation uses their children to hurt and control others. It is demonic.
My mom prays. That's how she is handling it now. She just keeps giving it to God. There were times when it seemed impossible. Now, however, she is actually seeing her grandsons again and will be spending some time with them in Disneyland over New Year's. God is more powerful than the strongest feelings of pride and hate.
Lord, I ask that you reach into the lives of nlp's son and daughter-in-law and open their eyes to Your love and truth, that You make them aware of the importance of grandparents in the lives of their children, and the value of a parent's love. Bring peace to nlp and offer strength through this season, so that when You bring restoration, no trace of bitterness will remain in any heart. I ask this in Your precious and holy Name, Jesus. Amen.