just a couple of things...first of all, if the military is not notified immediately of the divorce(or separation, legal or otherwise)when they are notified, your mother-in-law's ex husband will be required to pay back all BAQ(it's BAH now, btw) and com/rats(rations pay) from the date that she moved out of the shared domicile. I know this to be true because it is happeneing to my husband...we are separated, but he waited a few months to do the paperwork because he did not want to move into the barracks and now wants me to lie about the date on the paperwork, which I won't do, so he's having to pay back BAQ and rations...This will not affect your mother-in-law in any way except that they take it directly out his paycheck until it's paid off, which means that he gets no paycheck until it is paid in full, so any monies due to her as a result of the divorce(alimony, etc.) will not be recieved until a later date as he will have NO money at all...you might want to have her tell him this.
Second-- since they were married for a significant amount of time, duriung which he was enlisted in the military, she will be entitled to half of his military retirement check, as well as death benefits under SGLI unless she waives that(which I would advise not to do) Since they were married for so long, if she does not work, then she may be entitled to more than half, as most members who retire from the military work for another 20 to 40 years after they retire. This information comes to me by way of my stepdad. He was in the military for 21 years. six months before he was discharged, he got married. They were married for 8 years, but only six months of that was when he was in the military, but she still gets half of his retirement pay every month.
not sure if this was what you were looking for, but I hope it helped!
Melissa