A to Z Challenge: L is for Loneliness

Welcome to the 2013 A to Z Challenge!
This year, I’m focusing on two themes:  Emotions and grammar,depending on which letter we’re on each day.
I’ll be sharing mostly what I’ve learned about writing emotion into a novel, but I’ll also be throwing in a few key grammar lessons, pet peeves I’ve picked up while working as an editor.
Today’s an emotion day. 
__________
L is for Loneliness:  affected with, characterized by, or causing a depressing feeling of being alone; destitute of sympathetic or friendly companionship; isolated.
I had to write about this emotion a great deal in my own novel, The Mistaken.  The main character’s wife dies and he feels responsible.  Immediately after, he isolates himself, even when there are many people around him, his friends, his family.  No one can take the place of the one he loved most.  A lot of the time, that’s how loneliness works.  I wrote a short passage at the end that deals with this feeling:
“It was disconcerting to be among all that was so familiar yet feel that the heart that beat within my chest was not actually my own.  I was lost, like a child separated from a parent in a large crowd.  Not alone, yet quintessentially lonely.”
And in the middle of the book, when the sight of another woman makes him miss the one he’s lost:
“I spent more than a small amount of time propped up against the wall, watching her, studying her face, so beautiful, so peaceful in sleep.  I knew I shouldn’t be watching her without her knowledge, but I missed having that kind of beauty near me.  Having it so close, yet knowing it was not mine, was a bitter pill, but I felt as if I’d been pulled back through time, back to when Jillian was still alive.  I was unbearably lonely, and, at that moment, Hannah filled me in ways Jillian once had.  It was difficult to turn away from something as alluring as that.”     
This shows how loneliness is not about solitude, but rather about isolation, feeling separate, emotionally divided from the whole.  A character can be in a room full of his friends and family while they festively celebrate a momentous occasion, a birthday, a wedding, yet even among all these people, who likely love and care for him, as the very symbols of happiness swirl around him, he feels the most lonely. 
This type of contrast in imagery and emotion can be very effective and relieve the writer from having to rely on clichéd and overused body language.