The Little Engine's Tough Decision

I don't have enough self-esteem left to make it up the mountain. The only way I can imagine reaching the top is if I climb into the furnace and burn myself up. Fuel for the fire burning water into steam, powering the engine until I'm exhausted in a puff of smoke. I think I can... I think I can... stop. Clang. Clank. Clunk. Stopped in my tracks. This sucks. It's cold and frozen up here. I'm going to die no matter what. Goodbye people that I have hauled this far. Either I unlock the coupling or burn myself up.