For me it is the wall...
Today I am not building the wall, instead I have taken the day off to look at what it is that I am doing and why.
The wall goes up to protect me and depending where I put myself, sometimes I have to build it ever higher.
The wall was begun a very a very long time ago when unfavourable elements attacked me and I was left hurt and feeling vulnerable, so I built a little wall to protect myself, but as I became bigger, over time the wall became smaller so I had to build it bigger until finally it became a monster and although it did its job of keeping out all that was unwanted it left me isolated, until one day my spirit broke the wall down into rubble and I climbed out, but had no protection whatsoever and a terrible fear came and I began to build the wall over again; but building a wall takes a long time and so I am vulnerable and too sensitive because I relied on the wall all my life...so I sit and think about all this...
My favourite writer used to be Richard Brautigan and then Rumi, but these days it's anyone I can find that is a good read...