The EU political situation is probably a bit weird to outsiders. It's weird enough to those who live there...
Here's a short description
It all started out as the Common Market. That was free trade area where European countries had no taxes on goods imported from neighbouring countries. Everybody agreed that was a very good idea, and it worked well.
Then they thought, "OK, that worked out well, let's go a step further". This led to certain agreements about marine borders for fisheries, common agricultural policies, and so forth.
Then they figured "Let's go the whole way (but we won't tell anyone what we have planned)". It morphed into the EU or European Union, which at first was just a talking shop. But somewhere in the bowels of Belgium were people who had grander plans. The thing is, Europe has been in a more or less permanent state of war for the last thousand years, so after it seemed to work out with the trade agreements, and there were communication channels for discussing these issues - some nascent federalists began to dream of a Federal State of Europe.
Apparently no one objected enough because it began to act like a whirlpool - everyone got pulled in whether they wanted to or not. Certainly, the British politicians lied prodigiously about the real plans, as they were well aware that Brits like going on vacation to Greece but getting in bed with the Greeks was a different story. So like Corryvreckan, the whirlpool pulled everyone inward and nobody could escape. You can hear the roar from a long way off, but it just sucks you in...
And then one day people woke up to find they had an EU that made their laws, and no EU laws could be altered by the people, and the laws were made for giant transnational industries and smaller businesses were crushed by the rules, and they had thousands of bureaucrats in Brussels and Strasbourg making new rules all the time, and the European parliament could only decide on laws and regulations that were of no importance to anyone, and the real laws were made in secret committees, and the corruption was so bad that everything cost double as the bribes had to be paid first, and the EU Commissioners bought their job as it was worth tens of millions, and it became the world's most successful corruptocracy, and a Commissioner would aim to make $100 million before retiring, and the main thing traded and sold and bartered became the votes, and public health was sold off to the pharmaceutical industry, and joe public realised his role was to work hard, pay enormous prices for everything, then get sick and pay for the pharma drugs, and then die 2 weeks after retirement so that his pension did not have to be paid. And everyone in Brussels had a picture of uncle joe Stalin on the wall as he was their role model, and they prayed to the Kremlin for inspiration whenever a problem came up, and they realised that Europe was now just an outpost of Moscow and everyone was happy except for the public as they had been sold to the highest bidder.
And there were a couple of countries like Switzerland, Norway and Iceland who thought, "We don't want to go to Greece anyway as it's way too hot", and they had their own micro-EU trade group, and they traded freely with themselves and with the EU, and so they had free trade in the EU and none of the murderous corruption and open borders and disastrous monetary union and the mickey mouse Euro and the free movement of terrorists within the rest of Europe and the wine lakes and potato mountains of idiotic central planning done by blind cret_ins with an IQ of 43, and generally had a very good laugh at the rest of the idjits now tied up in a monster experiment with neo-communism and the huge and corrupt bureaucracy that inevitably accompanies it but that apparently no one had foreseen as they were too busy kissing the feet of uncle Joe's statue.
And the poor, imprisoned people of Britain looked longingly at the EFTA group of Norway etc and wondered how they had been so royally shafted. And the PM spoke kindly to them and reminded them their place in life was to pay taxes and die young (but that bit was cut out of the speech as it probably wouldn't have gone down too well), and as he sank another glass of Hermitage Grand Cru and puffed on his second Montecristo of the night, Dave silently pondered his old friend Tony Blair who had taught him so much about neo-Stalinism and how it was the answer to everything: iron control of the production sources and the revenues by the clever new method of federal control, which meant nobody could even argue the toss any more, and have the tobacco/pharma/public health mafia kill anyone who gets in the way.
It was just wonderful, and he gave Tony a final toast: La vie en rose, baby!