I personaly think that Catilina was a better man than you give him credit for, we all know the stories of his depravity and his desire to bring down the state but how much of this was really true or was it just fabrications by Cicero who hated and feared Catilina more than any other Roman, Cicero hounded Catilina's every move and had a helping hand in blocking any attempt Catilina made to further his own political career.
I'm not saying the decision of rebellion that Catilina took was the right one, but he was definately forced into it, a similar situation to Caesar and the Civil War, great men, proud Romans like these two will not simply take a step down and admit defeat, they will see their beliefs out to the bitter end because in thier eyes it's the right thing to do.
Years after Catilina's death even Cicero who hated him showed his respect for the man.
"He had many things about him which served to allure men to the gratification of their passions; he had also many things which acted as incentives to industry and toil. The vices of lust raged in him; but at the same time he was conspicuous for great energy and military skill. Nor do I believe that there ever existed so strange a prodigy upon the earth, made up in such a manner of the most various, and different and inconsistent studies and desires."
From Cicero's Pro Caelio