Life is unfair... really unfair, that was the one and only thing going through Mark as he barely trotted along the path into the unknown.
He was not hungry, no... hunger is something you describe when your tummy rumbles and you want some food, this was much, much worse, his body was wafer-thin, you could not only see his entire ribcage but also all the veins and what one would call muscles although calling them that would already be stretching the definition of the word "muscle" to its very limits.
Mark barely could keep his form let alone orient himself with the surrounding, as far as he was concerned, he wasn't even walking in any direction, he was just... moving, he was too tired to make sense of anything.
He fell and darkness overwhelmed him.
It's not easy being a changeling you know, not only everypony hates you from the day you are born (well, maybe except your own kind) but there's not much you can do about it either, as you have no choice on the matter.
Ponies aren't the only ones that always hated changelings... all creatures hate changelings and why? all because of that stupid habit they have to change into other's loved ones and feed off their positive emotions.
You could say it's unfair, sure but would you blame a wolf for killing a fluffy rabbit? would you blame a bear for hunting cute seals? would you blame dragons for eating rare and precious gemstones? and besides it doesn't have to be this way, sure love is the most filling emotion of all but there are also others like, joy, compassion, or even friendship which is the next best thing.
Of course for emotions to nourish a changeling they must be directed at him (or her) directly, but who said that changelings have to pretend to be somepony else? why can't ponies be friends with changelings as they are? that would surely work, after all changelings are like any other pony once you get to know them better... and it's not like the changelings actually drain these emotions, they only feed on the emotional energy that has already been given off, which nopony else needs.
One would say that this makes no sense as the changelings could simply live off their own emotional energy, however it is most unfortunate that they are unable to feed off the energy of another changeling.
As for death... it is not as simple for changelings... when you die, sure you go to heaven or hell but you still exist, and normally the same would apply to changelings when they die of any cause apart from hunger.
Normally a soul of a being (be it dead or living) emanates a form of emotional energy that enables them to simply continue to exist in some way or another, (which explains ghosts and other apparitions) but in the case of changelings its a whole different story.
Changelings for unknown reasons are born into existence with more emotional energy than any other being, however they are unable to emanate this energy which means that at some point, if they run out of the energy, they will simply cease to exist.