I came here to say this.
Once you realize that life has no meaning, except that which we arbitrarily assign, you can only go a few ways with it. Of all the 'ism's you could choose in that moment, absudism is perhaps the least worst.
"Credo quia absurdum est."
What you're describing is "existentialism", and Camus's absurdidm is a reaction to it. The difference is subtle, but important to Camus.