How do i strengthen my ankel? im 16 stone and in december 2007 i landed hard on the side of my foot from a?

hight of abowt 18 inches and seveerly damiged the ligaments.i then spent 15 weeks on cruches, now neerly a year arfter leeving the cruches behind,im still limping most of the time, 2 or 3 times a week my ankel gives way,and i end up on the floor in agony also harf way up my calf my achilles tendon seems to tear and i need to take strong pain killers for the next 3 or 4 days to enabel me to werk it is reerly distressing me i just want my normal life back plese help (ive had physio)