Lyric discussion by VictorPF 

Cover art for A Life of Possibilities lyrics by Dismemberment Plan, The

So, I can't figure out who "they" are.

The rest of the song seems pretty straightforward. Sounds like the main character is breaking away from the past, showing independence, there's no "light to lead the way"

They try calling, you don't answer. You come back to them, but nothing is familiar anymore.

So who is "they"? People holding you down? Your old friends/old lifestyle?

I'm new at this song-interpretation thing, so let's go for no flaming.

It's about the world ending due to nuclear explosions and after he comes out of his shelter, there is nothing but "Earth in all directions." Nothing is familiar anymore because everything is taken out by the explosions and "They" are the people and politicians behind the decision to nuke.