Farage said that if the Leave vote lost buy a narrow margin (like 52% to 48%) that he'd fight for a second referendum.
Is there any chance the Remain side can? Please? Pretty please, with sugar on top?
Imagine you are in a partnership with 27 other people. You are one of the most influential partners and contribute the third largest amount of money to the partnership. As a result you've received a lot of special considerations from the other partners as conditions of your membership. One day you march into a meeting of the partners and in a fit of anger you flip the double bird and shout "Fuck you all. You're dictators who are ruining my life. I quit!"
A day or two later you have regrets and ask to be allowed to return.
First of all: why would anyone even consider letting you back in? Second of all, even if they did let you back in, your influence and credibility among the other partners would be destroyed. They would never believe you, never trust you, never fully accept you. You'd be a shadow.
There are three ways the UK returns to the EU:
1. In the reconstruction phase after a catastrophe like a global financial collapse or a war in Europe. The surviving European nations come back together in order to rebuild, yet again. Third time's the charm, right?
2. After everyone in politics associated with the Brexit is dead of old age. Then credibility can be restored because those responsible are long gone.
3. In pieces. Scotland, then Northern Ireland, then perhaps Wales and England. Again, this will take many years.