"Despite all my rage, I am still just a rat in cage!" Smashing Pumpkins
If there was one universal trait in the LOST main characters it was "pent up rage."
Jack had a burning pit of anger about his father's treatment of him. Christian refused to acknowledge his accomplishments; failed to treat him as an equal; belittled his leadership qualities.
Sawyer had an active volcano of rage in his sole life goal to avenge his parents deaths. That rage changed an innocent young boy into an adult murderer.
Kate had a sea of troubled emotions. It seems that she felt smothered by her rural upbringing. She became quite upset with her stepfather's treatment of her mother. Her emotions turned to psychotic rage when she blew up the house in order to "save" her mother from future abuse. But when her mother rejected Kate and Kate's reasoning, Kate seethed inside.
Hurley also had a mountain of bitterness induced by chocolate candy bars as a substitute for his father abandoning him as a child. Without his father's influence and direction, Hurley never finished anything in his life. He was angry about it, but so depressed by his fate he did nothing about it. Instead he developed the excuse that he was cursed.
Locke was angry at the world. He also had abandonment issues. He never fit into the foster homes. He never fit into his school teacher's vision of his career path. As a result, Locke had no path. He wandered from meaningless job to meaningless job. His anger made him a loner because he could not keep friends or girlfriends, which made him even more upset. His anger led him to become selfish - - - believing his only self-worth was to get his own way (no matter how crazy it seemed, such as being wheelchair bound in the outback desert.)
Even Bernard was an angry man. He was upset that after a very long time, he found a woman, Rose, who loved him. But soon after, fate gave Rose cancer. Bernard was angry that the cancer was terminal and he would in a short time lose her forever. At some point, Rose herself, was mad about her medical condition. She took all the treatments, but nothing worked. It was after the plane crash, when she was sitting alone on the beach, that she came to terms with her plight.
And this may be the symbolic or allegory of the series.
The plane crash was a symbolic mental crash inside the characters to get them to focus in on more important things - - - like survival, their fellow man, people who need them. The island was symbolic of a treatment plan, alternative therapy or mental reconditioning protocols which gave the characters the tools in which to deal with their rage issues. As the series wound down, the characters were not self-absorbed with the issues that caused their internal rage, but they were focused on helping each defeat their collective demons and get off the island.
There is a corollary to this anger management resolution. As I have written in the past, I always thought that when Rose was sitting alone on the beach, she came to terms with her plight and knew everything would be alright because the pain of her cancer was gone. Rose at that moment knew the only release for that pain was her death. She came to terms with her death immediately. She then knew that the others around her had to deal with their issues in order to come to terms with their deaths, in their own way. So with that knowledge, she went along in the background knowing that she would be okay in the end.