Here are some good things to think about. (disclaimer: I have thrown in the occasional sarcastic barb for spice, but mean no disrespect...)
You are wanted here. Support is available. Apostates are not evil. They just left JW's in the same way they left their former church to join JW's. It didn't make us evil then, and it doesn't now. That is Lie #1 about apostates. Most are VERY good people.
Give some thought to your screen name. You might be a doubter today, and a believer or an apostate tomorrow. Either way, doubt is a transitional phase, not a surname. You might hate gays today, and be gay a year from now. Things change.
While Bethel probably wades over here on an approved computer from time to time, they do not track down most people, unless they post their full name and picture. Which is a pretty dumb thing to do. So don't do that, and you can post as freely and anonymously as you want, unless you are a kid still living at home, or have family living with you still in as a dub.
....so don't post anything too personal on here and you'll be fine. Use your name if you want, encode it, call yourself Gandalf, it doesn't matter. If it is a typical "Jeff", "John" or "Sue" type name, I doubt that will put you on the radar at all. There are plenty of JW's with your name.
You will see the occasional heated debate/flame war on politics or on something even more important, like the last episode of CSI. Don't be scared. If people's opinions offend you or you disagree with one particular poster, just be a grown up and ignore them. You aren't changing their mind, assuming they have one.... Post on other topics.
You can make the experience of being on JWN or other JW boards as positive or as negative as you want it to be. If someone doesn't like you, who cares? They don't even know what you look like or what you are doing other then typing in front of your computer at the moment. No sweat!
Share your story. Share your doubts. Be prepared to grow by accepting the fact that JW's are not the source of 100% truth. And that non JW's have some excellent takes on life and opinions as well. And that can possibly help you to figure a few things out.
Peace!
