God, that's terrible. Dual-booting is always risky for exactly that reason. Hopefully you've got backups of all your stuff (even if you can't use your raw fl-studio files anymore).
Even as a Linux nerd myself I can't give you any solutions, but I know how it feels because animation software on Linux is equally hot garbage (my only options are: a paint program with animation tacked-on, a video editor, a 3D modelling software, and an animation app with the worst UI in existence).
In those cases, I think your best bet is to just grab another PC that'll do the job, install Windows 7 (get an extended kernel patch if you need to), and almost never connect that sucker to the internet. Because for as neat as VMs and Wine are, they're not good enough to be Windows replacements.
That or beg Image-Line to high heaven to make a Linux port of FL-studio, but I don't think that'll go anywhere.
Best of luck with your endeavours.
RusNG
That's so unfortunate, I'm so sorry for you. I hope you have a chance to make music again in the future if you still want to do it.