How can I go back to my old school?

ok well I changed schools because i was having a hard time adapting to the fact that me and my long time boyfriend broke up ... but im in grade 12 and i realize that i miss my old school, and i want to graduate with my friends, but now my parents wont let me go back; well my mom says she doesn't care, but my dad is worried about my reputation, and thinks i'll look indecisive, but everyone at the schools only think that i moved because i wanted extra credit and i could only get it at my new school, so how do i untangle myself in the mess ive created? and go back to my old school where i belong?