Depression help

I came here to talk because I truly don't know where else to go to for help. To make a long story short, I've been struggling with depression for several years. I've definitely experienced my ups and down. Considering how deep my lowest got me, I would say I'm much more stable now. But lately I've been feeling so low. I feel like I try so hard for people but I'm never enough. I continually go out of my way to be kind to others but I'm often mistreated in return. In my honest opinion, i love who i am as a person and im very proud of myself for my kindness and the respect that I give to anyone i meet. Im always wanting to help others and cheer them up. Despite this, I feel so worthless. I feel as though maybe I just don't matter to people. I'm so alone and i have nobody to lean on for support. I just feel so lost and extremely lonely. I don't know what to do.