Walls : Do we really need them ?

He is all pine and I am apple orchard.

My apple trees will never get across

And eat the cones under his pines, I tell him.

He only says, "Good fences make good neighbors."

-- Mending Wall by Robert Frost 

Frost asked us when we were kids if those walls were really required and so why do we continue to build them ? I don't just mean the ones between countries and communities, those are inevitable. I say inevitable because of greed and a constant need of power that we as the human race have. Besides those I am asking about the walls we build, around us: among friends and family. 

Walls that restrict us, walls that hold us back, walls that make us lesser human beings than who we are. Why build these and when built why not really look at them and destroy them ? People on a daily basis create layers of walls, from prejudices due to color, race, religion, behavior, egos and just about anything to stop them from interacting with others to the fullest. 

I built walls around me for years, to protect me from the world or to protect the world from me. As I destroy each layer of these walls I feel like a stronger, better individual. But then I meet people, people who I consider a part of me, people who I trust. They push me unknowingly to recreate these walls , either to protect them or to protect me from them. Now I wonder why ? Do I create these walls to maintain my relationships or do I let them down to maintain me ? 

I say I don't need these walls and I will not let anyone make me  create them again. I don't want to build anything that hides me from the world, because my apple trees do not go across to eat his pine cones ...