You're in Scotland right? I think voting SNP is required to prevent the Brexit party. The issue with that, is the SNP do plan on using this to ask for another independence ref.
It looks like UKIP are going to crash and burn anyway - most leavers will vote for King Farage.
I lot of people I know are looking for guidance on how to vote tactically to prevent UKIP / Brexit Party getting lots of seats. We need a hero.