How?

How do I move on from an 8 years relationship? I'm not even trying to get likes or reads on this post, I'm seriously concern about my mental sanity after breaking up with what I thought was the love of my life.
I have lived what you could call a difficult and full of obstacules life, yet, when I was 14 this amazing sweet boy came to my life, he fought for me, even when I wasnt allowed to have a boyfriend he was willing to do all the sacrifices necessary to have me in his life and save me from this nightmare I was living in, he said he was here to show me happiness, something I hadnt felt in all my life... I believed him.
We had an amazing relationship from the most part... but, after the amazing was done, the terrible came along... it wasnt only bad, it was awful, as penetrating as a knife in your chest. What you thought was your salvation resulted to be only as bad as everything else, not only that, you had hope, only to be taken away in a single blow.
If you take a step back and listen to your breathing, you can feel your heart being ripped out from you.
I dont wish this kind of pain to anyone... Not even all that people that I would wish to disappear from this earth, but right now, I'm still stading in from of the long fall, thinking, should I take a step forward and end it all? Or... should I just stop believing in it all?.... what should I do? I dont think I can come alone with another option, when u feel as desperate and sad as I do, you can understand, you cannot see any other choises, even if they are in front of you. I dont think I can trust on good will anymore, I took his hand, and after I was on my feet smiling at him, he just tackled me down....
I need help.