have never heard anyone say that I was an ex-Catholic or an ex-Lutheran or an ex-Baptist. They just stop going to their church and don't talk about it.
Putting it bluntly, because they were not suffering under undue influence in their lives. They did not have their autonomy restricted by an organization that claimed to love them but in actual fact was extremely damaging within every aspect of their lives.
In other words, they weren't in a cult.