The Tory party is in a war between two main factions: one that votes for economic competence and one that votes for cultural values. No Deal Brexit makes it inevitable.
Theresa May had three years to avoid this war. She failed.
There is no compromise possible with them. So, fiscal conservatives have to suck it or leave.
Hence the Tory civil war.
But it also creates problems for Labour between its two main factions.
Labour's two main factions - those that vote for socialism and those that vote on cultural values - are also split.
There was a brief civil war among Socialists, but the Lexit side lost.
Those people are moving to the Lib Dems because they want a strong anti-Brexit voice, which is now a totemic cultural issue, and Corbyn doesn't provide it.
The accusations of anti-Semitism also put off many who vote on cultural values (but largely, not socialists). Made it easier for them to stomach the Lib Dems too.
Those who want economic compentence may live with No Deal if they mistrust Corbyn more. Of they will defect to the Lib Dems too.
But I don't think he recognises the challenge ahead of him. I think most of his advisors are focused on the economic argument and don't understand the culture wars.