I honestly believe the Governing body do not force anyone to shun. People shun because they are shunners, many a witness in good standing I have known to ignore thiis commandment from the G.B, and I believe it's because it's simply impossible for them to shun, it's against their nature, and they don't do it.
That's not to let the G.B off the hook,trying to inforce the evil policy.( the reason it is done is to control information, and keep the community away from worldly association, hence celebrating birthdays and Christmas is a shunning offense) Its also not a blanket condemnation on shunners, some do it simply because they believe it's the right thing to do. But my observation congregations were like a pack of wolves, made up of people who enjoyed hurting the weak.
To clarify those that have shunned me, must take individual responsibility for shunning me, blaming an organization doesn't give them a free ticket.