what happens when a diabetic eats sweet things?!

No they don't, I am type 2 diabetic diet controlled and I eat sweet things with no side effects. Carbohydrates is what diabetics have to be more careful with than sugars because it is harder for the carbs being turned into energy than it is with the sugar. Basically my sugar levels will rise but if the rest of my diet is controlled it is ok, I still take sugar in my coffee and on mothers day I did eat a lot of chocolate with no side effects except feeling sick because I was a pig.

Not all sweet things contain sugar, artificial sweeteners are fine. If a diabetic eats too much carbohydrate, especially in the form of simple sugars, their blood sugar rises. They may also become ketotic and dehydrated eventually going in to a coma which can be fatal.

GP for more years than I care to remember

it depends on their type of diabetes.
it's all to do with blood sugar/glucose levels, if they eat too much the body cannot produce enough insulin to keep the sugar under control, they can just feel a bit sick, or if left out of control it can result in a diabetic coma and death.

other people's diabetes mean their body produces too much insulin, this means they may have to eat sugar to help keep their blood sugar levels normal. if their sugar levels go out of control it usually results in sever shaking, fainting and can result in organ failure.

have a look on the NHS direct website for more information

If its sugar free, then the person is ok, when they eat sweet stuff made from sugar( synthetic or natural) their blood sugar level will go up and is in danger of having a hyperglycemic attack

Nothing will happen. But it's the carbohydrates that will higher their blood sugar.

Diabetic