If you don't have enough liquid cash reserves or income that you are forced to sell a "coin or two" every now and then, you are doing it wrong.
I would have to agree with you. I was of the mindset to keep more cash in reserve but my husband figured Bitcoin had a better "return" than the crazy low interest rate the bank offers so we decided, albeit foolishly, to go ahead and keep our reserves in Bitcoin and pull from there when needed. Seemed a brilliant plan until we have had months of downward movement. On the upswings it is amazing though.
The only comfort is that we never really had much cash on reserve until we began investing in BTC, so really, it isn't that big of a deal. It is just that our BTC value isn't the same as it was a year ago.
It was @ $240 exactly one year ago
But it's true that we were in a strong up trend back then... 
