In many marriages, particularly traditional ones, one spouse earns and/or controls the monies, and the other does not. Where the spouse with the money files for divorce, the other often feels at a disadvantage, financially speaking. They meet with attorneys and tell them that they do not have money for a normal divorce retainer. Too often, they meet with an attorney lacks the experience and knowledge to properly advise them as to their options.
In fact, the Probate & Family Courts in Massachusetts are specifically authorized by statute to "level the playing field" in these circumstances. Massachusetts General Laws c. 208, Sec. 17 states that "The court may require either party to pay into court for the use of the other party during the pendency of the action an amount to enable him [or her] to maintain or defend the action,...". In short, your spouse can be ordered to pay your lawyer's retainer, as well as pay the balance at the end of the case.
I have personally used that statute to help clients bring or defend actions that they thought they would never be able to afford, including non-divorce actions, such as paternity/child support actions. This statute is a great equalizer, and is under-utilized by many attorneys. One caveat though: the other party has to actually have the money or the personal ability to pay: If your spouse has no liquid assets and borrowed their money from a relative, you cannot get an order for attorneys fees without showing that this borrowing is a normal part of their lifestyle.