how do u leave one life to live another?

every day I dream of leaving the man ive been with for past 2 years...
but I don't want to hurt him.
ive lived torn like this for a long time...
my heart yearns to be with a women who understands me...
yet I live on auto pilot living with this man that pays the bills, allows to me to drive his cars, and makes sure we have food on the table...
so how? how can I want to leave him. how do I weigh the pros and cons of this man who says he loves me...
do I stay or do I go???