I've been where you're at. If I can just echo what others have said DO NOT discuss doctrine.
Unfortunately, the people we THINK we know so well, the ones we THINK love us and can handle the truth about "The Truth" are the very ones who turn us in to the elders or open their mouths out of "concern for our spiritual health". This is a very slippery slope. Once you open your mouth, you kind of can't take it back. You may find yourself on the business end of three elders asking you if you believe this is god's spirit directed organization!
My experience is sort of like CHG's... I did, however, open my mouth to my parents because the fire inside me to tell them the truth (that they are in a cult) was eating me up and I just had to tell them! I didn't just blurt it out, but after reading a lot, I was armed when the conversation presented itself.
Even full of alcohol, my dad defends the organization. He has an excuse or a twisted convoluted reason for every point I bring up. My mom is too naive to know any better and even though she has accidentally admitted that my points made sense, when she realized her faux pas, she got angry and shook her head and told me in an angry and shaking voice "I will NEVER believe that! I will NEVER let you break my relationship with Jehovah!". So... I fucking give up, honestly. This all happened while I was living under their roof and hadn't been to a meeting in about 6 months, nor out door to door.
I spent months dodging the elders... Their phone calls, their pop-in visits, etc. Twice they came over uninvited when my parents weren't home and I told them I was busy and had no time to talk. Avoid Avoid AVOID! I do have to say that my dad was pretty cool about things...when they would approach him and tell him they were going to come over on the weekend, he'd tell me ahead of time so I could make myself scarce. So 9 times out of 10, when they came over, I wasn't there. My dad's a MS and my mom is a pioneer...but they both knew the repercussions if the elders found out how I really thought. So in their own way, they protected me.
I moved away a few months ago. I moved in with my boyfriend, I'm incredibly happy, and I still have the freedom to speak to my parents because I haven't been DF'ed, nor have I DA'ed. I haven't set foot in a Kingdom Hall in over a year, haven't gone in service, haven't been to a Memorial or an assembly or convention...and I feel SO FREE. I knew it would feel good to be completely out, but I didn't know it would be like this. My boyfriend encourages me to look into whatever interests me, whether it's science or witchcraft, aliens or atheism. I can read what I want and WATCH what I want without having to look over my shoulder and wonder if a JW will see me...because if they do, they have no idea what my background is, so it wouldn't matter to them anyway lol.
I've made some friends here. My bf introduced me to some of his friends and I've made some acquaintances at work. One of the women the bf introduced me to actually studied with JW's and went to meetings for 2 months a long time ago and she got a very weird feeling and knew exactly what it was and beat a hasty retreat. So she pretty much understands me in a lot of ways. She said she couldn't imagine being raised like that and then marrying into it as well. Her sister-in-law married a JW and is now in the midst of a divorce. So this woman "gets it".
I guess I'm saying this because the one real way you can leave the org without losing your family is to keep your mouth shut and get out on your own...preferably a distance away from people who know you so you're free to be who you are and pursue what you want to pursue without being scared that you'll be spotted. Don't be afraid of "worldly people". To be honest, a lot of us here are now considered as such and you have no problem talking to us and "associating" with us, so just take it into real life.
Keep us updated and let us know how things go for you, whatever you decide.