Quickly Changing.

I remember when I first started posting here, I was lost, very depressed, and lonely. I always thought, “I am not going anywhere in life. I just want to turn 20, live on my own, and kill myself!” After being on here for a while I started to feel a bit happier, soon after I began therapy and started to fell more happy, more confident, less lonely, I started being more hopeful about the future and had plans for what I want to do. But here I am again, a few months later and I am back to being depressed, I have isolated myself and now I regret it. I am not even hopeful for the future anymore, it’s like I am back to the same plan. Why does the idea of killing myself after in a few years sound so… right?