scrubs of the heart

i know i've attempted nursing twice now.
i know i quit both times, each time using a different reason and excuse.
in my time driving home tonight i had a LOT of thinking time.
i kept thinking about work. about school. about what i want to do in each aspect.
i think i realized why i was ok quitting both times.
for the longest time i couldn't figure out; i loved it and couldn't get enough of it during my high school classes. what changed?
in high school i was constantly around it. each semester in class. each semester in clinicals.
i wasn't working at the time.
in college i was working during anatomy. i was spending all free time helping out at my church.
that seemed like the logical transition.
so i did it.
when i was working at the church and started school again, i was still spending all my free time elsewhere.
these last two times i wasn't surrounding myself with it.
i'm afraid that once i start working at the hospital, and am around it all the time, that itch to finish will come back.
shoot, i haven't even started and just thinking about it has made that itch surface again.
i want an easy, clear cut, right in front of me, answer.