Chrissy's Birthday

So today is Chrissy's birthday. She turned 18 today, I can't believe she is already 18...it's crazy. But what's not crazy, she is my parents perfect little princess. I love her to death and would do anything for her, even if after she graduates we don't talk for years and she finds me and needs something, I would drop everything for her. But, right now, I don't even know why I try anymore. I woke up this morning to make her breakfast before mom and her went to a movie, but my breakfast wasn't good enough, they were going to get food together before the movie. I bring her a slush home from work (Sonic) and it doesn't seem good enough either. My mom came in and asked me if I was going out or if I would be here for dinner. All I had to do today was work, nothing else. I rarely have plans on Mondays in a normal week. If I had said I was going somewhere or not going to be here for dinner I wouldn't have heard the end of it because it's precious Chrissy's birthday and everyone has to be here for dinner, but I still don't here the end of it because I am staying for dinner. I dont' get it.
What does everyone want from me? I hardly ever ask my parents for anything, but the one time I could use their help or need something they can't help because it's Chrissy's birthday and they're time, effort, and resources are going into that. I don't know why I even try. I have come to learn recently that not only is she their precious princess, she is also perfect in their eyes, and she is all of that because she wasn't the mistake and they don't regret having her and she isn't a disappointment. Why do I even come home ever? Why do I sit through family dinner after family dinner constantly being interrupted by someone who thinks their thought or story is more important than what I have to say every single time I open my mouth? Why do I make sure to get off work on time so I can make it home and not be late to family dinner and then sit around and not get to eat when Chrissy works until she gets there? Why do I tell Nicholas and Brooke (my cousins) it would be a good idea and would impress everyone if wait to start eating until everyone is at the table, then the one time I'm the last person to the table and they're telling everyone to wait because I don't have my food yet, everyone starts eating and just ignores my presence? Why do I try to take my sister or family to church, then come Christmas Eve it's mandatory that everyone go to church together, as a family, or come time a boy comes into the equation she goes three weekends in a row? What's the point anymore? I'm sick and tired of trying and getting things thrown in my face and never being right or good enough for anyone. I let it go almost ALL of the time, but last night and today was too much. I'm sick of it! It will never change or help anything, so why waste my time and energy on it anymore? I've deicided it's not worth caring or trying anymore.