My one friend's mom has diabetes as well. She has been living alright with it for a number of years now as well. Follows the strict diet (for the most part), goes for regular walks, is in her forties, and doing pretty alright.
As long as you follow the doctor's advice, and keep stress levels low, there is no reason why you shouldn't live long and happy.
Sweetners are not tough to get used to. Heck, I use them as well and I am not diabetic (although I once had the symptoms for a loooooong time, but thankfully found out that they were there due to a stressful job, which I eventually moved on from).
I have another friend whose dad lived into his seventies, and he was diabetic for decades. It wasn't the diabetes that killed him though, it was cancer, and I must say, for a geezer, he was pretty healthy as well (until the Big C got to him).
Then there is a lady over here at work who is diabetic, who does NOT follow the strict diet, and also drinks too much at times, and smokes like a chimney. Well, she has been diabetic for about 2 years now, and normally looks pretty rundown. She does not wanna stop woth the cigs and booze though...