@Lash,
Lash wrote:... a British alliance with the EU.
I've missed that.
Until now, the UK is a member of the UK.
That would be finished with the 'Brexit'.
Afterwards, everything had to be negotiated.
The EU is for ‘full’ members only.
If you don't want it, you can get (after negotiations) an "associate membership". This gives access to the internal market with its free movement of goods, services, capital and people. You will only have to apply those rules and regulations that are necessary to create a level playing field in internal trade.
That also means you don't have representation and the corresponding voting rights at EU level but have to follow the rules.
Perhaps, there will be as a third possibility something new, just for the UK. But Norway and Switzerland, for instance, then would want the same conditions as well.