Falling into darkness and sadness...

Since that day I always had these feelings, of falling and not knowing how to get up or when I will do it. In my head the only thought that happens is grab that edge and cut yourself ...
Right now I am sitting on my bed, with the computer in my hands, trying not to hurt myself and clear all my feelings in a letter.
A while ago I found a way to get all the anger and anguish out of writing what I feel, and then read it and try to find a solution. It works most of the time, and sometimes it doesn't, but I try.
I made many mistakes so far this year, and mistakes of which I am sorry, very sorry.
I feel very sad and I am falling again where I swear not to do it again, I need that light in my life that illuminates my path between so much darkness, and that light I have actually found it, but right now it is thousands of kilometers from me So what am I supposed to do? I keep or stay, I sink or I swim, I go or I stay
I don't know, I just want to be fine for those who love me, but if I don't love myself and I don't forgive myself I can't go on, I'm so sorry.