Sitting on your hands and not doing anything with your investments is a very hard thing to do, especially in the face of relentless FUD!
Best strategy to avoid any emotional decisions is to have two stacks: one for long-term and one for shorter term trading/investing, which will alleviate that itch to "do something".
Reminds me of the quote "It was never my thinking that made the big money for me, it always was sitting”