Buying and holding during crises has never failed me. Dunno who you listen to. I've said before my biggest investment windfall in my life so far was dumping 2 years of my Army Iraq salary (like $93k at the time) into the market in 2008. That time was out of ignorance because I was a 20 year old retard.
Now that I understand it better. This time tells me start buying. But again I've always held and I've never sold anything yet. The market will absolutely recover. Just like it has done multiple times before.
But buying in now is just like
Blazin
says. It never feels good to buy in as it plummets because once it goes lower you feel like you missed out... which you do in a way. But not enough that it matters over time. Just need to suck it up.