Annoying step-brother and what to do?

Ok, so I live with my mom and her boyfriend and my brother and mom's boyfriend's two kids. Sometimes it gets very stressful... Especially every second week when Dave's (my mom's boyfriend) kids are here. Now, his oldest son Josh just turned sixteen on Valentine's day so he's about a year younger than me (I turn seventeen in two weeks). I have no problems with Josh. In fact, we barely talk. He's mostly in his room doing something with his technology. But Evan, the youngest... Man oh man. He's ten, he'll be eleven in April nd he is SO FUCKING ANNOYING! I can't stress that enough. He always has to be by his dad's side, he's not capable of amusing himself, he never let's my mom spend any alone time with his dad. He devours everything in the house, although most things he "eats" ends up wasted in the garbage... Food that could have been mine. He sleeps with his tv on super loud so I can hear it through the wall... He's just SO ANNOYING!

I honestly love Dave. He's an awesome guy and he makes my mom happy which is something she really deserves because her and my dad had a terrible relationship. I would love living with him if it was just him and Josh... But Evan honestly stresses me out so bad, I don't know what to do. First of all, I'm not used to having a kid around. The only sibling I have is my brother who's nineteen. There's never been any kids until recently. And second of all, this kid is the most spoiled, bratiest child I've ever had to deal with.

I just don't know what to do. I don't want my mom to break up with Dave, they're amazing together. But I feel like my attitude towards Evan is putting a lot of stress on their relationship, and on my relationship with them. Help.