"I feel that crying is almost - like, aside from deaths of relatives or whatever - totally avoidable if you follow two very simple rules: 1. Don't care too much. 2. Shut up."
We are shown Will's ideology from the very start of the novel, to convey that he lives by the certain rules that he sets for himself (which is evident throughout the novel). As he is the quieter of the two Wills, this quote portrays the reason for his silence - as an excuse for the inner turmoil going on in his head; this can be compared to the second Will Grayson, who can sometimes care too much and never really 'shut up'.
"i am constantly torn between killing myself and killing everyone around me. those seem to be the only choices. everything else is just killing time."
NOTE: the lower case letters are used to distinguish between the two Wills, just like in the novel. The quote itself is used effectively to show Will Grayson's attitude towards his life and the others around him - the way that he sees the world and himself. For the reader, when reading that quote, would assume the boy to have a mental illness of a sort, due to the depressive undertones and him thinking that suicide or homicide is the only option or meaning to life.
"i want to tell her that's what the voices in your head are for, to get you through all the silent parts."
Here, we are challenged with the concept of Will mentioning the voices in his head, which he understands as normal. The idea of him being schizophrenic has never been confirmed throughout the book, but there are constant references to the possibility. However, Will doesn't seem to mind the voices - he enjoys the fact that they're there to keep him company; which, in itself, conveys how deeply lonely he is and how he doesn't have the support that he requires.
"when things break, it's not the actual breaking that prevents them from getting back together again. it's because a little piece gets lost - the two remaining ends couldn't fit together even if they wanted to. the whole shape has changed."
This is a crucial metaphor in the novel. It suggests that mistakes are inevitable, people mess up and break the things that they care about without meaning to, and, even though the situation can be helped and 'glued' back together, it will never go back to how it used to be - because a little piece gets lost. In this case, the friendship can never go back to the way it was, because Will is too hurt by what happened that he can never trust Maura again. No matter how much she tries, and even if she is forgiven, there will always be a presence of unease and an underlying pain in the friendship.
"You like someone who can't like you back because unrequited love can be survived in a way that once-requited love cannot."
This quote, again, shows Will Grayson's attitude towards love and pain that comes from certain actions. In this case, the author portrays the repressed hurt that Will keeps inside, refusing to date, solely based on the fact that the pain that comes from mutual love in a relationship produces more suffering than when the love is one-sided, as you are not vulnerable to the person and they have limited effect on you - therefore allowing 'survival.'
