The Lib Dems were annihilated in the 2015 general election going from 49 MPs down to 8. The electorate could not work out what they were actually for, apart from being a drag on the Tories in coalition. Nick Clegg was never forgiven regarding his false promises on tuition fees by the younger voters. They could not wait to punish him.
They now have the grand total of 9 MPs. Their anti Brexit stance will gain them some support amongst remainers but this USP will certainly fade away once we have left the EU. If the fixed term parliament is adhered to the general election will be in 2020, well after the divorce would have been completed.
The Labour Party is an on-going car crash. Even if Corbyn is removed, with the present Labour Party voting system, another left winger will be chosen. The LP will probably need another electoral defeat to force the National Executive to make the necessary changes so it broadens appeal.