Just be honest. You're not out to hurt anyone, you just want to know the truth and you have nothing to hide. You've done nothing wrong, so don't let them make you feel like you have.
If they come to talk to you, just tell them you don't have time, that you're very busy and you'll have to get a hold of them when you have some free time (and just don't call back). You can probably do this along with pretending to not be home for a little while until you feel prepared enough to state clearly how you feel and what you want to say.
I feel for you and I'm feeling sort of anxious inside because I know it's going to be hard when I'm in that situation. Just know that you're not alone and we all have to make our stand for truth. Funny how I used to think the same thing about the organization I belonged to.
Good Luck (I mean that)
Anne
"When caught between two evils I generally pick the one I've never tried before." Mae West