bad life

hi my name is umair ad i am 21 years old my story of life is very unique when i was 5 year old my cousin said me that she loves me she was just 4 years old and now our love is 17 years old this is very strange we started to love each other when we did not know the meaning of love but i think we started to love because we born for each other i was living very happy life with her but at the start of this year my cousin told me  that her parents are looking for a good boy to marry with her i became frustrated and i told my mother that i love my cousin but she say i will never allow you to marry her she is not a good girl .but the fact is that my mother met with her just one time and i know her from 17 years i know she is the best girl i ever saw but today my mom says even if you die i will never allow you to marry her i am very dippers ed i love my mother she is very good but i cant leave my love i did not tell my love that my mother is not supporting her instead i told her that  my mother will come to your home to talk to your parents after 2 years .i am very sad i lied to her for the first time in my life because i can not see my love sad. now i do not want to live, my friends says that you are very talented dont waste your life you will become good for humanity but frankly speaking i have no feelings in me i never feel happy my mind remains confuse everytime i started to forget things like what i have eaten one hour before i don not know why my mother is doing that with me, my brother went to america and he married with a girl and did not tell my mother but when she became aware of his marriage she did not scold him,my another brother have three crushes and my mother supports him and now he is living happily with his love but, she scolds me every time that you are interested in a girl  and etc.i post here because i just want to know a way to end my life i dont want to live more than 8 months but i want to end my life by doing something good  e.g some  social work or something else.please suggest me??