I can give you one - Overcoming depression is like being in a dark cave. You cannot see any light and despite this stumble around and hit your head on rocks. People yelling on the outside tell you it's in your head but you can't see anything b/c it's so dark. Eventually you make the choice to just start throwing rocks around in this cave. Eventually one sparks. You stumble around to find this particular rock but may never find it. If you work really hard and with some luck you can find that rock again or find a new one and light your own way out of the cave. Not everyone finds their light rock (flint). Some won't make it out of the cave. But you can always rest assured there are people out there who were given flashlights that will go into the caves hoping to bring someone out with them.

You may have to paraphrase this