I'm actually struggling with this one myself. I was baptized at 15,. but by the time I was 19, I was inactive. It is now ten years later, I've moved to the other side of the country and I do not identify as a Christian at all. I practise Nichiren Buddhism these days. I hoped that my family would want to understand how I got from point A to point B, but they've expressed a desire not to even try to understand who it is that I am now.
It is rather exhausting and discouraging to talk to them, the conversation becomes one where they only want to know that I exist and haven't died yet. They don't seem to actually care about what it is that I do with my life since the world is coming to an end anyway.
My goal is to have a channel of communication with them that is at least respectful, and that I can trust has a chance of remaining open. I think that they are realizing that my current course is not just a phase, although I have told them this from the start. It seems as though they are ready to shut down the lines of communication. I'd rather not have that happen.