I have departed from the teachings of the JW religion that I was raised in because I no longer believe those teachings and I also speak out against them. Therefore, I am an apostate. This puts me in the same company as Jesus and the apostle Paul who apostasized from Judaism.
What makes the word apostate more palatable is the history of Christianity is one in which one group after another after another after anothere has apostasized from the "mother" church.
Look at Charles Russell: The established churches of his day accused him of heresy (a "nicer" word than apostasy, some would say).
I eat you/you eat me/they eat us/they eat each other/we all eat eveybody else....