weighing 28st , the 31-year-old , feared she would not live to see her wedding day .
for most of her adult life , miss mccormick 's obesity meant had been in and out of hospital , suffering with life-threatening asthma attacks .
doctors warned the strain of being overweight would kill her if she did n't slim down - and fast .
now , the pair are engaged to be married and have bought a house together .