It’s not enough to be against something. You have to be for something better. – Tony Stark
- Jules goes behind Connie's back, so she can do what she wants; so she can feel free. In Friend or Foe, she lied about doing stuff with Valery, buying the dress, etc. And in Crash Course she asked Buck to teach her to drive because she wanted it. Jules has a hard time saying no to the things she wants. Even if she knows what she wants is wrong, she'll do anything to get it.
-Buck goes behind Eugene and Katrina's backs because he feels it's necessary to lie in order to help another person. He did that in Old Tricks with helping Eugene, and in Crash Course with helping Jules. Buck has a hard time saying no to other people. He knew he wasn't supposed to help Jules learn to drive, but he did anyway because Jules asked enough, and he wanted to make her happy. He also pretended to not know how to drive so that Eugene could teach him. He goes along with things to make others happy.
I think both of those things are a reflection of how they were raised. If Jules ever wanted something, she A: Went out and got it for herself, or B: Simply asked for it.
Buck, however, grew up putting Mr. Skint's wishes over his. If Buck was sick, but Mr. Skint needed him to drive a truck at eleven, there were no questions asked. He'd suck it up and do it. As I hear more of Buck living with the Meltsners, Buck is realizing, that Buck and Skint weren't partners. On the contrary, Buck was Sink's slave.
-In Friend or Foe, Jules says to Connie, "You don't get me!" She was really saying, "You don't understand my interests, you don't get why I want to do these things, you don't get me."
-In Crash Course Buck says to Eugene and Katrina, "You don't understand me! You probably never will!" Buck's not saying, they don't understand his hobbies, or why he does stupid teenager stuff. I think the "We know what's best for you" line triggered anger. See, when Buck said, "You don't understand me!" He was really asking, "Why weren't you there?! Why weren't you there when Mr. Skint hit me for the first time, when I spent Christmas alone, crying in fear of my guardian? When I hit myself for the first time? If you're my parents, if you care about me, why weren't you there?You don't understand me because you weren't there for most of my life. You don't understand me! You probably never will!"
Buck's outburst was so incredibly important. We saw a little bit of his non-carefulness in Old Tricks, but it really came out in this episode.
I also want to address the fact that when Eugene was talking about Buck trusting him, he wasn't talking about Katrina and him. Buck trusted Katrina a while ago. There's no doubt there. However, with Eugene, I think Buck's had a difficult time trusting him, simply because he's a man. After how Mr. Skint treated him, Buck's naturally wary of male authority figures. So, yes, showing vulnerability with Eugene is a big, important step in their relationship, and in Buck's character.