first things first: first ask your self a few things that i have listed, then plan your case accordingly.
1) do you want to live with her or not
2) if no..then be prepared to pay maintainence. as simple as that, if you want to stay, then fight your divorce case.
3) maintainence case is like a never dying leech on a husbands body, who has to carry that parasite until his death, so stop worrying for what you cannot get rid of, until and unless you have strong solid proof of her income which is at present and not in the past, however it all depends if the past employment is argued well by your lawyer. then it also can be dismissed.
4) calculate your money: check your income and expesenses. see and judge for yourself if the maintainence you are paying is affordable to you, it is futile to fight and pay your lawyer if you can afford to pay maintainence. as i said before. the leech cannot be rid off so easily. so weigh your options.
i am giving you practical advise. not technical....so it is upto you to decide.