Depression... Brain, please stop thinking!

Mum and dad, I think my depression is back and am a little tired of life. I'm not sure whether I should tell you this, which will make you unhappy. I know all this while both of you didn't give any pressure to me in anything. All the pressure I gave to myself one. I just don't want to lose. I'm afraid of losing. From my experience with my ex-gf, I could clearly see myself so weak. I couldn't blame her. She showed interest in the beginning. Maybe she just got bored of me. The current one might end up the same even though she isn't my gf yet but the situation is just about the same. I feel she is gradually losing her interest. Maybe I shouldn't find a partner but I'll feel lonely and unhappy also. I also don't have many friends. I'm not doing well in my career. I'm not doing good as a son and as the eldest son. I just feel that I'm not good in anything. I thought of ending my life several times... even though I know life is precious. Everyday there are people who die of starving, disasters, accidents and diseases. I really know that I have a lot of things and I should be grateful. However, I agree with the phrase "Happiness is not based on what you own but it should come from within yourself". If I still can't find my happiness, I think it's useless even I can live until 100 years old.