I've dealt with severe depression (still have moderate depression) and can identify with everything you're saying. I disagree that the lingering thought of things getting better is stupid though. Hope is a good thing to cling on to, though extremely exhausting. The longer you hold on the easier it feels like it is to let go.

There is a song lyric that says "hanging on to hope by a thread." I really identify with this.

You're not worthless garbage. I know saying that you aren't doesn't help because I don't know you, but it's true. Loneliness definitely magnifies that feeling though. Sorry if I came off as a know it all. You are stronger than you think.