You are right, it is God's earth and Tina is His child. He cares and will do what is best for her. It is also His Heaven and those who believe have a place there, even those who are not "a very good Christian".
Never second guess God, He is in control and He loves us more than we can know. Sorry if I sound preachy, but I am serious about people's lives.
Father, please help Dave and Tina. I ask in Jesus' name. Amen