Why Does Life Have To Be So Hard?

I am going through so many emotions in my life, where I am at the point that I dont know how to handle them. I feel almost lost in my own little world. I'm a emotional rollar coaster. I've always been one of those people who put on this tough front and fake smile to make everyone think that everything is ok. When in reality, it's not. Deep down inside Im hurting, lost, and confused. I make choices in my everyday life to make others happy and not to dissapoint them, but when will I start making choices for me, and for what I want in my life, and say to others when they look down on me for not making a choice that they wanted me to, to say "hey, for once I am doing this for me, because this is something I need to do." and not care and live in the moment of finding some sort of peace within myself. Im always trying to make everyone proud of me, I never really stop to say hey go do something to make yourself happy for a change. And everytime I try doin that I always end up hurting someone in the process. I cant win. I'm 18 now, so when am I going to start making choices for me, and only me, and stop worrying so much about others? Reality is setting in more and more each day. Im considered a adult now, a lost and confused one, in need of finding herself. And I dont want help doing it from anyone, because I have to search within myself, and no one can help with that because its something only I can do. I love everyone who has stuck by me through all the struggles, happiness, and so on. But now I have to start making decisions for me and for my life, and if I make a choice you dont like, promise me you wont look at me any differently and still love me or care for me like you always have, and just relaize I am doing this for me, and there would pry be a good reason as to why I make some of the choices I will in life. I just needed to get all that out........Im going to bed now. Thats been bottled up in me for a few months. Thanks for your time.