Proof that there are NO rules as far as centering everything on a wall! Haute Indoor Couture: Portfolio
How to disguise off center windows.
Off center windows behind bed disguised by entire wall of airy white curtains
Disguise an off-center window with draperies! More
Window treatment behind bed makes it appear that there is one centered window, when in fact it camouflages an odd, off centered, window. Perfect!
I use this trick and love it. "Faux window" treatments add balance and symmetry to an off-center, one-window wall. I would put Christmas lights around the actual one and the fake one so they're both lit up. Maybe just the fake.
How to hang drapes over an off center window!
bed off center window - Google Search
jill of all trades, master of none.: Faking It
Hiding an off center window behind bed.