Help ive lost love for my gf?

i dnt no if i sud carry on wth my girl freind because shes all ways goin on about how she loves me and she does any thing for me but i just dnt feel out for her any more and i dnt wont to hurt her but i all so dnt wont to keep on living a lie and and keep lieing to her and i hate lieing to people and ifi was to finish with hr i dont no the best way to do it with out messing her up cos of her gcse's are so close