This is how I know I'm not resigning, I'm retiring. Giving it all up and moving on to do something that is me and makes me happy. It's been great, it's been bad, it's been awesome and it's been totally frustrating but the experiences gathered make the pains of the journey worth it.
When something isn't worth it anymore, you cut your losses and move on instead of staying with it and whining about it on a daily basis. So that's what I'm doing; gathering what's left and moving beyond it to a better place.
It definitely doesn't mean goodbye; it only means starting over.