435lbs dieting need help...?

I have been overweight my whole life, I weigh a whopping 435lbs 5'8 26 y/o female. I'm scared of losing my life and I am dedicated to making a change. I know diets don't work, I need to change my lifestyle forever! My question is where to begin. How many carbs how much protein, how many calories. Its all so confusing for me because every site on the web has their own version.. I need help.. please guide me on the right direction..