I remember when this happened. I was just a kid and it was a chilling sight and news that I wish we'd talked about more, but I was probably too young for that talk. Or my parents didn't want to deal with such a tough subject.
Cults are no joke and I'm not joking around. If you can't leave your religion you may be in a cult: http://culteducation.com/help.html
Get Help if you can.
Now I may be an Atheist but that doesn't mean I equate all religions with cults. Hyperbole aside, most religions and most religious people are not going to make you drink poisoned kool-aid, but that doesn't mean they aren't unhealthy in their own ways.
Your health, your decision.
Cults are a different matter altogether. In a Cult your health is not your decision - it's the decision of your religious leader(s).