Fed up of life....

I'm 21 n studying in 1st year of medical.... But for some months, im often depressed.... i wonder why we live.... wats the use of studying etc.... even though medical is the only thing i can do, coz i have the abilities, n i like helping people... but still sometimes i feel like leaving everything, everyone.... why does it happen so.... it sounds light here, but its really hard for me sometimes..... i remember some months ago i used to be happy, to enjoy life.... n i was a wonderful person.... but since last year it all changed... i had hard time coz m living away frm my parents, but with my bros who dont much care abt me, n my oldest brother used to be very strict to me.... i think living like this has made be become wat i am.... i dont understand myself anymore, i dont know what i want to do in life.... can anyone help me out?

hi...
i can understand ur problem yaar coz i too experienced the same.... so if u wanna be like as u were b4 take help 4m ur friends.., spend lot of time with them so that u can divert 4m all.., make friendship with good people who can understand ur feelings....... keep smiling n take care