Advice me please

I am a 23year old female. My parents
died when i was 8 yrs and so i dropped
out of school because no-one could
afford enough
money to pay my fees.
I then met this
guy when i was 14 and he
struggled to send me back to school. He
was selling fruit by the
street just to pay my fees. He then got a
job as a truck driver and
continue to send me to school even to
the university, of which i
am eternally grateful to him for… indeed
there are angels made by
God to help the needy in times of
trouble.
My problem is that i feel i can’t continue
with this
relationship because he is not my type, i
am not the girl that i used
to be when he first saw me, dont get it
wrong, i am honestly
appreciative of what God has used him
to do in my life but i just
cant get totally committed to him
based on pity or how he helped me. So
im
thinking How best can i tell him that he
is
not my type without hurting his
feelings?? I
am grateful that he sent me to school
but
i can’t be in a relationship with him
anymore. I want somebody of my own
class not a truck driver.
Please Advice me