You've just described an abusive relationship. The EU should make people want to be in it, not afraid of leaving it. Are other EU member states OK with being bullied and threatened in this manner?
"Remember that the EU isn't just about the fat cats in Brussels. It's also about bringing the people together. Europe has historically been the most divisive and warlike continent, with neighbours at each others' throats since records began..."
The creation of the EU may or may not have helped to bring peace in the beginning, but there's no reason to think it has anything to do with maintaining peace today. We have the UN, NATO, and the unimaginable destructive power of modern weaponary keeping the peace between nations in Europe today. Heck, even the "World shrinking" power of the Internet probably plays a bigger part these days.