"As for me...I don't know what I will do anymore. I've always told myself if I'd lost her I would be done...but she made me swear to not ever do that." I said that about someone that I loved greatly once... because when I was hitting my worst, it was someone who entered my life that I could hold on to. I won't question you feelings, but love comes in many different forms... and one of those forms can develop from the pure need.
We broke up mutually, with time, we went our separate ways. I was ready for it, ready to try again on my own... a year later, I started breaking down even more.
I will say one thing, we can only rely on ourself to hold ourself together. We can meet people in life we love, and we can meet those that we hate... but it all comes down to you. You said she was the one that gave you hope in the world... maybe you won't love another like you loved her, but do you think there's no other that can give you hope again?
If you've already decided not to get up again, then just do what you're doing, you've already given up, and you'll continue to go nowhere. You can either decide to let your life reach a stand still, or you can pick yourself up when you're ready. Because we all change with time, and change brings about new attractions, new people, new experiences. Change can bring happiness, and it can bring sadness... it can bring nothing if that's all you let it bring.
We can spend all our life hoping to never be hurt... but no matter where we go and what we do, things will set us back. Sadly, we can't have everything we want, everything that we think we need... you never need to stop loving her... the you of the past can always love her as much as you do now... but maybe the you of the future can find another love, another reason to move forward... another reason to get back up and keep fighting.
I wish you the best, whatever you decide to do. Hopefully with time things will get even the slightest better. I'm not preaching to you your emotions or how you should feel... because if we could logically choose how to feel, then things would be much easier. Whatever happens, happens, and I hope some day you can look back and find that the 12 years of suffering... or horrible experiences... has shaped you into someone you're proud to be, and has in some farfetched way brought you to a life you're happy living.