Only way I imagine it could happen is if a no confidence thing can actually trigger a GE? If that’s true your only hope is the pro EU Tories who by now should be completely disgusted with May’s direction and LDs plus the Labour MPs wholly on the pro-EU side (guessing these would be the ‘Blairites’) all basically saying “fuck our possible futures” and forming a new party whose sole claim is to ignore the result and stay in the EU.
I mean as a group they might be able to trigger a GE as mentioned above and then hope they will be voted in to quash Brexit with the support of NI and SNP MPs.
Sorry I’m on my phone here so this is even more hand wavy and muddled than it would otherwise be.