The Drum Of Your Steel Heart (Alphonse Elric x Reader) Fullmetal Alchemist

5 Parter-SPOILERS- Set as canonically as I could make it (with definite detail changes)
You are a child of Ishval, passing through the system as a refugee, having inherited extraordinary alchemical power from your mixed raced mother you grow up under the care of a Amestrian solider and you go through intense training, becoming the second youngest State Alchemist.. second to Edward Elric. The Fullmetal Alchemist!
You have sauntered through your alchemical career with relative ease, runnings errands for the State, fighting small fights and doing your best for the fairness of all in Amestris and the surrounding lands. Until the Fullmetal Alchemist and his dashing suit of armour brother show up. You are assigned together to investigate shady goings on in Central City and deaths under the hands of a rogue Ishvallan called "Scar" .. the rest is history.
Following the events you know of, you go through the entire saga of the Fullmetal Alchemist alongside the Elric brothers as a close friend and comrade. You form a particular bond with Alphonse Elric. Your trauma and insomnia keeps you up at night, and one night you find out Alphonse cannot sleep, so you decide to experience most sleepless nights together. You play chess, study alchemy, do puzzles, read and write together. You grow closer and find your heart and mind easing around Al. Even though you're older, he teaches you to be softer, kinder, more patient.
It's a bond you share with him leading up to the events before the battle for Amestris, you and Al are separated from Ed. You hold down the front line in Central while Al rushes off to find Ed, under your insistence.
You plan to end your life, using a strain of your mother's alchemical power she taught you to only use when you have no other way out, it comes at the cost of your life. The only thing you remember is Al's goodbye. A flash of red. Then darkness.