Well, I think that depends entirely on your own beliefs. For some people, their purpose in life is religion - to live by what they follow and be content with that. However, I get the feeling you're needing more than that, otherwise this question wouldn't have been asked? Well, firstly, I just want to assure you that you're not alone in questioning life. I mean, it's confusing, right? Wondering why in the world we're here, how we got here, what the point is of us just living each and every day. I completely understand why it's frustrating for you, and why you're questioning it. So many of us do.
Do you really need a purpose and a reason though? I mean, we're here. We don't really know why (unless, of course, you have personal beliefs that counter this) and we're not born with any real goals or destinations - we make them as we grow up. Do we really need a purpose? Can't we just be content in living the life we do have, despite the fact that we may never know why we're here? The fact is we are here, and there's not much we can do to change it! You can spend each and every day questioning why, of course, but I reckon it'll only confuse and frustrate you further, y'know? It's my personal belief that we're not born with a purpose - humans aren't here for any other reason other than to reproduce and life their lives - but that doesn't have to be a depressing thought! You've got your whole life ahead of you, to do whatever you want with. It's yours. You might not ever know why you're here, why any of us are here, but would it be possible for you to just embrace the life you do have anyway?
However, if you need more than that - if you need a reason and a purpose and all of that, then why not just live for your dreams and goals and aspirations? Surely there are things you love doing and there are things you'd like to achieve in your lifetime? Why not make it your purpose to do all of that, to live your life to the full and have a bloody fantastic time whilst you're here? I don't know why I'm here, but I do know that I'm going to make my time here absolutely brilliant, because we're not around for long.
At the end of the day, I guess it's just up to you. You can find your purpose in something grand and reassuring like religion, or you can accept that maybe, there is no reason or purpose for our existence but be content with that - it's not a bad thing, is it? Or, you can make your own purpose, which, I suppose, you'd do anyway - whether it be through religion or striving to achieve all your ambitions and goals and desires, or, simply, doing the things you love and going to bed each night with a smile on your face, y'know? Embrace life. You might not understand why we're here and what we're supposed to do, sure, but that certainly doesn't mean you can't have a good and happy life.
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it's broken beyond repair. it's in a million little pieces.