Could you give him a version of the post you posted here, OP?
You sound like a loving wife who is seeing this as a joint problem, but as you rightly say, he's going to go to an early grave, or at the very least suffer the mental or physical toll of lack of sleep and stress. He's been going two years like this now, it's probably another year or two max before the reckoning will come.
In some ways, your niceness isn't helping, in that you are not setting any boundaries around his workaholism. I realised I had to be quite assertive with my husband who was a workaholic when we met, we agreed on two nights home by 7, and one day on weekends as family time. This is not much by some people's standards, but it was better than waiting til 10/11 every night for him to come home. Think about what you want from him and then ask for it.
He also cannot cannot, however much he says he can, be working to full capacity on so little sleep. His work can't be as good at midnight if he's had two hours the day before and the day before. He's addicted to working, but his work will take even longer due to going slower in his down periods. He's not superman.
The funny thing is that ever since my husband took some time out and spent a few days a week caring for my dd2, he's been much more into home and family anyway, and is less of a workaholic, it may be if your husband dares step off the treadmill, he might like it and start to see how being the boss means he should be determining what happens in his place of work, not dancing ever longer and every harder to the tune of others.