how?

how do i heal myself? Why do i always think the worst when i know that things are never as bad as I make them out to be. Every day when I wake it seems like i start over again. As if i forgot everything that I learned over the past year. Is my depression that powerful that I can forget all the good things and feel overwhelmed with darkness? A black cloud overpowers me and tears down all my defense. I am helpless, yet at home. Can I overcome that black place that pulls me down and tears me apart? It breaks me down until i am that helpless child, trapped and powerless. No memory but the overwhelming pain. The more i think about the more it drags me down.