What is it with teenagers???

I just don't get it. I know I didn't like anyone but other teenagers when I was one but I don't remember being so nasty to my Mom or anyone else that was older than me. I had respect for them. My son is just being cranky and nasty and foul-mouthed today and I don't like it one bit! He has been told not to eat in the living room, everyone knows that is the rule, but he continually disrespects our rules and then gets mad at us when we confront his behavior. I really want him to stop or suck it up and admit he's wrong. Not gonna happen I guess. I'm just trying not to let him push my buttons. It's hard! I didn't think it would be so hard to parent a couple of teenagers but it is. LOL I guess the joke is on me.