Ready to move on but I can't seem to let her Go? Lesbian Love!!!?

I am 21yr. old colleger student who has been in a lesbian relationship for 8months and it seems like we are tired of each other but can't be without one another (not sure if that makes any since). We argue ever single day it seems like as the days go by it gets worse........ I have tried to leave her but she tells me she can't live without me and I fall right back into her love web....... I believe that we both have dominatiing personalities which clash because we both a stubborn and likes to have the final word in all arguments. I love her but I am not too sure if this is what I want anymore... She is the first woman I have ever been with prior to her I dated only men and then something happened and I met and fail in love with her....My friends believe that I am just going through a phase... I don't know what I am going through.. Help!!!!!