"It was never anything other than an advisory referendum"
How many times must this be countered ? Due to a poor system it was legally only advisory, but that was irrelevant since it was stated that it would be acted upon. One doesn't spend a fortune on something one intends to ignore if one doesn't like the result. And parliament accepted this and started the process. So this advisory nonsense is a red herring, always was, but continually brought up as if it had some relevance by remoaners.
"Not something which should ever have been put to the people"
Of course it had to be. There's been growing discontent with this federalist agenda for ages. The government didn't have the guts to get out, parliament as a whole still doesn't and thus fail in their job of representing the opinion of the country, but clearly it was the will of the people they are supposed to represent and so it was necessary that their voice was heard. Fortunately Cameron thought it'd solve a problem for him so offered it. Government aren't usually that democratic but should be on major decisions.
Democracy is not preserved by stopping a democratic decision simply because some don't agree with it. That is the antithesis of democracy.
Whatever Farage intended when he said he'd continue the fight if it went the way of remain, it isn't really comparable to the damage remoaners are causing now. It was his "baby", his long term goal to convince others to get out of a federal Europe. He had no power other than persuasion and if he wanted to continue to do that then the effect on the nation would be subtle. And if he (or remainers now) wanted to call for another vote in a few decades time, then fair enough.