The people that don't want another referendum know deep in their hearts that they will lose hard this time. Whatever brexit movement there is pales in comparison to remainers now. We have had many protests demonstrating this.
I would be totally fine if they voted for leave again. No one could really be mad about it after the desastrous amount of misinformation last time.
But I totally agree with you. They barely won it last time and now they're afraid to lose the next potential referendum and all we get is pathetic excuses why another referendum would be undemocratic. Hilarious double standards.