my love

i am 16 now i loved a girl but she first loved one of my friend but i waited a year for her at last she said me i love you as she came to know that the one she loved first is not a good one bit i still has a doubt that she had not left him i think that she loves me more than any does as we had kisses and hugs and etc she is tellin to me that she is only being friendly but i has doubt on her but shes my life man i will kill my self if i didnt marry him .its like shes the whole world for me please clear my doubt