Could be that this friend is not lost to you forever. Seems like right now
this church group is filling some need in her life that she doesn't find anywhere
else. People grow, people change, that's life. If you want to maintain a
friendship some where down the line, let her know that you care about her
and will be there if she ever wants to get back in touch. Wish her well, and
mean it, that's all you can do.