The CONFUSING: I may be incredibly thick, but just what is the difference between nihilism and absurdism?
That's an interesting question. I never thought about it before, but the difference is mild. Absurdism is the philosophy that all humans are alone in a world that is irrational. Nihilism rather suggests one to become skeptic of their surroundings. Nihilism suggests that their is no "truth" in the world and their is no "existence". If you saw Inception, then:
Nihilism attacks the concept of reality, and Absurdism focuses more on isolation in an irrational world, but not necessarily a world that does not exist. I hoped my nonsensical babbling helped.
I'm not sure the word "suffering" should be applied to schools of thought.
And I was talking more about Nietzschean nihilism, in which there is a lack of objective purpose vs the kind of absurdism that Camus identified with.
As with all philosophies, they are open to interpretations and have lots of different definitions.
I'd love to continue this though. 
I said "suffering" to illustrate the darker points of nihilism, but clearly, through nihilism, one can question what they thought was "real" all along. For instance, Nietzsche used Christianity as an example for his definition of nihilism. I don't want to sound apathetic to those who share the beliefs in Christianity, but Nietzsche had established that religion provides people with a "purpose", once humanity reaches a point where they don't need religion, they lose that "purpose". Thus, everyone is struck with nihilism, but not necessarily in a negative way. I'm a big fan of Nietzsche, he was truly a genius.
Absurdism (which I wasn't aware of until you mentioned Camus), is similar to nihilism, as well as existentialism. Absurdism suggests that people will never find their "meaning" in life, cause no inherent meaning exists. In a sense, both philosophies are one and the same, but I'd like to think of "The Absurd" being a conclusive statement that was formed through nihilism. Nihilism is questioning truth, purpose, and meaning through our own perspectives. Nietzsche was bound by perspectivism. Camus states that there is no purpose, and Nietzsche states that we as a people must realize that there is no purpose (but also that it's a slippery slope). Once again, just the way I see it. I also see how both can be construed as the same philosophy, and for all I know, they probably are.