I am making this comparison between Colin and Holden because of the allusion made in An Abundance of Katherines when he is talking about Katherine 12 describing her as, "She was as rich as they come, but she hated being rich and loved The Catcher in the Rye, and she said I reminded her of Holden Caulfield, presumably because we were both self-absorbed losers" (205).
I like this picture because it looks like Holden is lost in thought which I feel would be similar to Colin because Colin usually sits quietly trying to figure out the theorem a lot in the book and this is what I imagined his expression to look like.
Colin and Holden are similar in some ways. They are both teenagers that are at a point in their lives were they have to decide about their future. They both stray away from home and meet very colorful characters. Most importantly they are dealing with these very heavy burdens that is the cause of their sadness. For Holden, it's the death of his brother Allie and this change of adulthood coming upon him which he doesn't want to happen. For Colin, it's the breakup of Katherine 19 and the worry that he'll never make something of himself because of the stark contrast between prodigy and genius.
This song relates to this post because it's all about not really fitting in, not mattering enough for the memory of you to remain, and how the feeling of wanting to break down is so tremendous that you need therapy. This relates to Colin and Holden because they both are outsiders to most people and the do worry about what they are going to do as an adult to really matter.
There are differences with between the two of them also. Colin is an attentive student who is wiz in every subject and Holden has been expelled from at least three schools for disruptive behavior and bad grades in almost every class except literature. Colin actually has at least one friend in the world and he doesn't push people away while Holden has basically no friends and he pushes everyone away as a defense mechanism. The most obvious one is that there is something mentally wrong with Holden, maybe depression. maybe PTSD, but for Colin he's only going through the depression of a break up. Colin's depression from the break up is not going to last forever, in fact he gets over it because he starts dating Lindsey Lee Wells, but the mental disorder that Holden has is going to be mentally scarring and it will take most of his life to overcome it.
In the end, Holden and Colin are teenagers who both have their own problems to deal with and have to figure out their way in the world. Their only comfort is telling their stories to others, like the Ancient Mariner paying for his sins by telling his tale of woe.