Ugggh. I feel your pain. My advice for what it is worth, go very slowly. Make sure they know without a doubt that you love them. Be a good person and be the best father you can be they will come around.
I have always been very close with my daughter, closer than most Dads. I stopped going to meetings several years ago. She goes with her mother. Things were ok until a couple of years ago, she is now in her mid-teens (a difficult time in any parents life) and will soon be getting baptized.
I don't really have a problem with baptism in general, however I do have a big problem with baptism into this organization. This means I will have to go to a circut assembly, my first in several years, to be there for her.
Believe me, I am NOT looking forward to this at all but she needs to know I will always be there for her, and I will. Even if I don't want to.
Just remember you are still their father, they will still love you. I think it is best just to do a good fade and not get the whole DF thing mixed in.