Another analogy about the EU and the 'sovereignty issue'

If I decide to give up going to work, I'll have a lot more personal sovereignty - I'll be able to decide for myself, without any outside interference, exactly what I'm going to do with my time all day long, seven days a week. The downside, though, is that the company I currently work for will undoubtedly cease to pay my wages and that would be something of a disaster for me, since I would no longer be able to pay my rent or even afford to eat. So I suppose I had better carry on going to work, while maybe agitating for better terms and conditions - and, of course, should the time ever come when the benefits of going to work are no longer sufficiently appealing to outweigh the attraction of being able to do my own thing all day long, then I know I will be free to simply hand in my resignation and walk off the job. If that were not the case then I would be no more than a slave.
Similarly, were the UK to leave the European Union, it would notionally regain a certain amount of sovereignty but it would lose the undoubted benefits of full access to the single market (unless it agreed to obey nearly all of the EU's rules - although now with a much reduced say over what form those rules take). However, should the time ever come when the benefits of participation in the single market are no longer considered by the UK public to be worth the price of having to adhere to EU legislation then the country will be free to exercise its ultimate sovereignty and leave the European Union - because that Union is, in the end, a freely made, democratically mandated one and not some kind of old style Empire which forcibly denies independence to its constituent nations.