If you see a 12 year old kid breaking into your car and you know he's going to drive it away and wreck it, do you let him do it because one day the car will break down eventually anyway? Or do you try and stop him?
If someone mugs you and steals your wallet, do you say 'you missed my watch. Oh, and I've got an iPod on my belt' as he walks away?
If you see someone bleeding to death in the road, do you leave them to it? After all, they'll die one day so what's the point?
If the answer to any of the above comes back as a 'no', ask yourself why you have already conceded defeat in respect of diabetes?
Get a grip of yourself and take responsibility. It is worth it for the improved quality of life in the 'here and now'. The future will still bring what it will, but at least you may be able to look yourself in the eye and say you did your best. As opposed to not being able to look yourself in the eye due to them not working.
I know I'll die one day. I'm OK with that (what choice do you have?). When it comes down to it, I don't fear death (though hoping it is a long, long way away

). What I don't much fancy one that is drawn out and painful where I have to entirely rely upon other people; if you are not entirely selfish, do spare a thought for how those that love you would feel about seeing you this way, especially if they beleive you've brought a lot of it on yourself.
Gary