I like 2 boys....whom shall i choose...plz help...?

i'm 17yrs...a boy who is 21yrs proposed me before 2months...i ignored him for many days but he impressed me a lot and i accepted him...he asked me for a date but i have no feelings towards him..i just like him...i never felt to kiss him though he is smart....i met another boy in yahoo answers and i chat with him everyday....he proposed me and i said that i was fixed with that boy..he said to be as his girlfriend and i accepted..we used to chat everyday....he asked to see my picture and asked my phone number and i haven't shown him yet...he has some personal problems and depressed...he said me that he's going to die and i was very scared....i cried a lot for him...without food and rest i spent my whole day crying.....i got no replies from him and i thought he was dead....in the evening he replied that he was alive...i felt relaxed and happy..i chatted with him for many hours and i felt very sad while signing off....i started to develop feelings on online friend and i cant live without chatting with him....i like both of them but i think i love online boy...our families and cultures are different....plz help.. .whom shall i choose.....i cant concentrate in my studies....