Is it normal to have a bad year for your research when you're a group leader? This year has been rubbish, with grant rejections, grants coming to an end, research staff leaving, issues with students... feel like I'm doing a rubbish job and not cut out for this

I can’t speak specifically to your experience. But when I get into this mindset I hold on to the certainty that it is temporary. Things will come together, but you won’t notice until you look back one day and realise that you don’t have those worries any longer.