Should i go with my brain or heart?

basically, this girl likes me and i like her, shes very confusing and broke my heart before, i havnt been out with her but i think if i do, im heading for disaster, my heart says stick with it, even if she gets flirty with boys and hurts me, but my brain says to just cut contact from her and get over her. i really realy like her but i think getting over her is the best option, but what do you think? risk everything? or just back away now save anymore heartache?