If you are diagnosed with hypertension- does that mean you have that disease forever? -

What if you tried really hard and you got your blood pressure in a good range and you got yourself off medications... are you still classified as having hypertension because you had it at one time?

There are ways to lower your blood pressure and keep it at a stable range. A regiment of regular cardiovascular exercise, nutrition low in cholesterol, fats,etc, and medications. It is possible to maintain a normal range of bp without meds by intake and exercise, but you must talk with your doctor before-hand. You will always be classified has someone with the history of hypertension, but not always a person with hypertension.

Probably. But the treatment can be totally trivial, such as taking a pill once a day, so who cares?