That’s much clearer, and much more insightful, thanks!
I don’t see it that way (big shocker, I know!) - I see him as honestly wanting to do the right thing, be the right person, and not necessarily knowing how. In short, I think his motives are pure.
I don’t see him trying to play a role and deciding to fuck anyone who gets in the way. I see him as wanting to play a role and not having the tools/experience to pull it off. Put another way: he honestly believed that “Aaron was in danger and that he had to do something”; not “He was looking for a way to play himself up as the grand protector and Aaron presented a viable means to pull that off”.
To see what’s going on in his head and his reactions, it helps to look at the pattern of betrayal that he’s experienced. Male role-models are important to him. When his brother got hooked he was first appalled, but then because big bro did it, he joined in. He had a sense that this was wrong (see the scenes with his brand new nephew), but faith that his bro would come through. When his brother 1.) didn’t but then 2.) kicked him to the curb, he felt betrayed. Big brother basically screwed him, and then left him to fend for himself. While you or I might have seen Big Brother doing what he needed to do, Charlie was too dependant on his bro as a role model to separate his own needs. Co-dependant, sure - but these are drug addicts - you shouldn’t expect Buddah. . .
Same thing with Locke: when Locke was “helping him” through the drug addiction, Charlie really latched on. And Locke did a decent job until he got tired of it and weaned Charlie. This could’ve probably been a good thing, but it was followed almost immediately (in island time) by a negative action. . . The automatic assumption that Charlie was using again, and the overly aggressive smack down. So the character that /had/ been trying to (seemingly) help Charlie pull his shit together first abandoned him and then betrayed him.
All, of course, in Charlie’s mind. I don’t think it necessarily excuses his actions (particularly not w/ regard to Sawyer), but it explains them. The actions that should be excused are his irrationality because hell - EVERYTHING is irrational on the Island, no?
Of course, we’re outside looking in, but at this point it seems like everyone should be aware that weird shit happens to everyone.
So is it understandable? YES. Is it Excusable? Maybe. And I have a difficult time coming down as hard on someone if I understand where they’re coming from, particularly if I feel that their motives are pure, and especially if the rest of the crew have been dicks.