I would take some action, whether it's delving into something, or at least doing some research, even if you have no clear idea what it is you like. Taking some action to me gives me hope. Waiting around and doing nothing is a recipe for depression.
You don't even have to quit, but look around, find prospects, prove to yourself that you can find another job if you choose to, and you may find your outlook becomes much brighter. It's a feeling of being in control of your destiny.
And hey, if one of those prospects looks like a more promising path, then all the better.