I'd suggest starting again. Get rid of the orthotics (or retain a small arch support that is soft and comfortable), get some more neutral trainers as that's perhaps important. I'd then get someone to do a full neurological assessment of your lower limb, perhaps even to the point of EMG studies as your history is not pointing to much else other than an overactive tibialis anterior.

Can I be blunt and ask about your weight? The tibialis anterior muscle only really comes under load as you land on the foot (walking, running) as it try to control the foot slapping to the floor. This is the part of gait that needs assessing. There may be a neurological reason for the dysfunction or it may be simply that it is trying to cope with a larger body mass. You have a history or unstable ankles? If so, both ankles? And if so does your mother and grandmother have any such history?