Be Christ to her. Or if you prefer; be Christ-like. Forgive everything openly - over and over again; 70 times 7 times a day. Don't show anger but patience, kindness, forgiveness, love, gentleness - no matter what she does or says; doesn't do or say. Be so incredibly loving and understanding that she doesn't know what to do. Never let her incite you to anything but unconditional love.
Refrain from preaching to her. Let your actions speak. Make her feel incredibly valuable and precious.
To quote an old cliche; you win more flies with honey than with vinegar.
Do this as long as it takes... Read the story of Gomer in Hosea.
Lord, bring your light into the life of your prodigal, What looks enticing in darkness looks shoddy and cheap when exposed to true light.
Father God, give your prodigal a heart's desire to know You. Woo her to yourself that she would long for fellowship.
Lord, I pray for a new heart and a new spirit and that You, Lord would capture the prodigal's emotions, giving her a longing to do and to walk in the truth. In Christ's name I pray. Amen.