So me and my girlfreind have been together fo little over a year?

I love her with all of my heart and i never knew what love was untill i met her. She loves me to and feels the same way but our relationship has started to fall apart and i want to spend the rest of my life with her. I don't know what i should do i don't know if we should try to rekindle the flame we use to have or if i should just let her go. I really need help....