Girl olny why is my ex gf wants a baby from me?

see i am 15 and she is 17 , and its hard on me bec i have cancer my so called ex wants a baby from me bec am dieing i have 2 years left of my life we are so are really close. u prop. thinking why are we not togetter bec she brake up with me jsut bec of my cancer she said it was so hard for her now she telling me she wants a baby i would give it to her but i am olny 15 and i dont want to make a baby but i will hurt her if i dont give her want she wants what do i do