Good Evening, I am an attorney with 8 years experience in military matters. I will be answering your question today. The matter of what retirement is owed to a spouse is not exactly up to the military/govt, it is up to the court where the divorce was completed. In your case, it may be that you owed her 37% of your retirement, depending on what your divorce decree/settlement says. The standard equation on how a court would have split the retirement would have been years in service while married, divided by 20 (or total years the retirement is based upon), times .5 (her half of the marital share).
For example, if you were married to her nine years while in the service and retired at twenty, she would typically be awarded 9/20 (.45) x .5 = .225 or 22.5% of the retired pay.
I am not sure where the 37% would have come from. I am guessing because there was a 10/10 in place, that you originally thought you were married for longer than 9 years?
In any case, the amount you owe is not decided by DFAS, but by your divorce decree, so you need to look at that to see what you owed her. If it is 37%, then that is what you owed/owe and the only way to get it changed is to go back to the divorce court (or to get her to agree to a modified settlement and file it with the court).
Also, if DFAS stops paying her directly but your divorce decree states that you owe her X% of the retirement, you will have to start paying her yourself. This gets tricky when your retirement is converted to disability if the disability pay replaces retirement pay, and you will need to speak to a state lawyer for the jurisdiction where your divorce occurred in order to determine the effect of converting to disability. In some places and with some divorce decrees, you can stop paying, in others you will have to continue.
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