I had a blue/black female once that flared at EVERYTHING - me, the cats, my mum, the keyboard, water glasses, the curtains.... The large females can get really aggressive and territorial. She also built bubble nest a few times. (I think she had gender issues, personally.)
As for the dyed betta question - I've had two light pink/white males. I got them when they where still really really tiny, and as they grew they developed black and red in "spots" not only on their body, but also on their fins - but it wasn't until they were about 6 months old, and the spots just kept spreading. (I had a white male with black gills turn into a red backed, red spotted finned betta. If I hadn't seen the transformation, I'd have thought someone switched fish on me!) Marble bettas have been known to change coloration as they grow, and this is probably what your female will do as well.