You know, I'd just look at it as she knew what her minimum requirements for a relationship are. Sure, people can learn to deal with less than they want but you should be grateful they were both honest about what they could offer/what they needed to be content, and that it ended before it began.
I think I have a pretty good handle on my requirements for how often I need to see/talk to new partners to not get unhappy or excessively lonely or to feel distant from a partner. Although I found I could make do with less than I wanted, I also believe I've kept from pursuing things that weren't right for me, which keeps both me and them from wasting time or ending up breaking up after a long drawn out misery of "trying to make it work".
I know you're probably just feeling affronted for your husband a bit *how dare you not know how awesome my husband is and want to date him!!!" but really I'd just look at it as she would've done you a disservice to not state what she wanted. It's also SUPER awesome that your husband knew what he could give and was honest about it too. Really if you read, you'll see a good % of threads are about people unhappy because their partners are trying to give more to a new partner than can be reasonably expected if they still want to be paying attention to their previous partners/kids/chores. I really suggest not being hard on her at all. Her "demand" isn't any more a demand than his "demand" that he isn't available as much as she'd like is one.
Happiness will never come to those who fail to appreciate what they already have.