First off, IMO it's possible to be a workaholic and emotionally available. But it's also possible to be both.

For me the question would be: why is she a workaholic? I've known and know a number of different workaholics. There are those who genuinely just enjoy work - but then, those are the ones who tend to also be emotionally available. Then, there are those who want to see themselves as important, possibly with some narcissism sprinkled in (definitely avoid that). Then, there are those who are control freaks, not able or not trusting enough to delegate work to others. At that point the question becomes why they don't delegate enough and what can be done there. Then, there are those who are workaholics in possibly the most literal sense of the word - they're having difficulties, often mentally, and they're using work as a distraction.

Going from there, the question would be: how important is she to you? How open is she to finding a solution? The most important thing is to talk about it, which it seems you have. But a part of that conversation has to be: what specifically will she change to improve the situation (and, possibly, what can you do to improve the situation)? "It will get better" is not enough. "I'll be handing X off to person Y, and I'm having him trained so he can take over starting Z" would be an example of an a concrete improvement. And if as soon as one thing is handed off the next comes on the plate, you have to look at what can be done to avoid the next things coming onto the plate. That is, assuming the whole thing isn't too much for you. It's completely legitimate to say, "I can't have a relationship like this, it will tear me apart".