Will Brexit cause the EU to collapse?

Britain is just one of 28 members. It is an important country in Europe, but the EU can function without it. What was then the EEC was formed in 1957 by six countries. Britain did not join until 1973. So it was 16 years without Britain being involved. The EEC evolved and more countries joined and it is now called the EU. The EU may need to reform as a result of the decision of Britain to leave, to change some of the reasons why Britain felt it should leave. It will take time for Britain to leave and there is even the possibility that they will decide not to.