I know it must be very hard to understand these things as a young Christian. I would like to suggest something to you....as one Christian to another. I am very aquainted with "family" churches. In many cases, it is not a good situation. I can tell you that you will be hindered by this D and this family as long as you attend that Church. You really would be "free" to focus on your spiritural growth by going to a different congregation. As long as you go where her family members are attending, there will be contention. You will be so distracted by the trouble within the family (which will eventually run over into trouble in the Church) that you will not mature in your walk with Christ.
I believe you are as earnest as any young Believer I have had the privildge of knowing. I would hate to see Satan win the victory in your life. He may get "this" battle where your W and the M is concerned......but he doesn't have to win the war over your life on earth.
Take care, Sandi
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!