Looking for tattoo idea

I want to get a tattoo. I know what I want it to mean, but I don't know what to get. I want it to symbolize that no matter how bad things get they can get better, and no matter how go things get they can quickly go bad again. Any input or concepts would be greatly apriciated. Thanks

hello-hey, I was thinking a ghostI know it sounds a little cheesey but, a ghost to some is re-birth (a good, a temperary state) and to some a ghost is death ( a reminder of how bad it could turn)-what do you think?