Feeling low

I feel so terribly unhappy. I almost do not know anymore. I'm horrible about it. Have been for a long time. The good days are becoming scarcer. Everything is so heavy, so black. Has to do with my horrible mood swings. Sadness, aching, frustration, loneliness. I cry all day long. I always change my mind and feel like I do not know myself anymore and no longer know what to do. Just cannot enjoy things anymore. Everything feels wrong, physically and mentally. My study is on a very low pit and I actually fail with everything I do. I have no relationship, not even real friends, and contact with my family is almost impossible. I do not know which way to go. What I do must. Everything just feels wrong. More and more, the thought comes up to me to stop completely. By jumping from a flat or for a train or something, I can finally get rid of this dreadful life and nobody will miss me. But yes, I know that is not really a solution. I just do not know anymore. Just being incredibly unhappy and do not want to go through. I just cannot go on.