I don't understand why, but this has helped me get 3 kids back out of the organization (after dragging them in from birth)
I would say things like...I just read <pick one, Rutherford's,russell's>book, and it was very interesting. I just read the Society's Proclaimer's of God's Kingdom book, page number or chapter whatever. I just read <watchtower/awake/issue whatever. Don't tell them what it says in advance if you can help it.
What I've been saying to Witnesses i meet, "My heart goes out to Jehovah's Witnesses, this is a difficult time for them. Seven failed prophecies, child molestations, etc etc. God bless you in this difficult time." or something to that effect. it tends to open the floodgates!
If you give them permission to be a Witness, they can't wait sometimes to get out. Maybe some other posters on this board can give insight into this.
Life is a roller coaster. Get in, sit down, shut up and hang on!