Hello again!
I commend you for not rushing into the fray, bent on destroying your wife's belief system especially, as you state, when you have no other to put in its place.
One of the reasons your wife may become silent when you open a conversation is that her core beliefs are nothing like those of other "Christians". She knows that, if only because she's heard it said so many times at the Kingdom Hall! What may seem like a simple question to you may seem to her like scaling Mt. Everest conversationally; she would first have to bring you up to speed on how JW's understand many different scriptures before she could get down to the topic under discussion.
If you questions to her are concerning why people leave JW's there is an even more compelling reason: if she knows "too much" about the topic she could be thrown out herself! JW's are not given much information when a person is removed from good standing in the organization (disfellowshipped or disassociated). A one-line announcement is made stating that so-and-so is no longer a member; after that it's all rumor, speculation and gossip. If the ex-JW tries to contact a JW in good standing it leaves the JW open to a charge of apostacy for dealing with someone who is no longer on God's side. JW's do not tolerate "apostates" or anyone who has dealings with them. The JW definition of apostacy significantly differs from that of other Christian denominations, if not in fact than in deed.
You will soon note that the people on this board have left WT/JW's for a variety of reasons. From experience I can tell you that no matter how outrageous or outlandish their stories are most of them are true and unembellished. Keep that in mind because if you continue researching why people have left Jehovah's Witnesses you will read some harrowing experiences!
Last note: There is a private message function on this site. Look near the upper left corner of your screen, find the box with your username in it. That's where you will find notification if anyone has sent you a PM. To send a PM to someone on the board just mouse over their username (found to the left of their post) and follow the instructions you will see.
OK I lied...this will be my last note! Sometimes this board erupts like Vesuvius and WWIII combined. Don't let it bother you. Keep reading, keep posting.
Best,
Nina