Female Troop Divorce Up Slightly, Male Rate Largely Unchanged

I my 34 years of military service less than 5% of the married soldiers I served with were married to other soldiers. For many of those marriages one spouse left the service within a few years after marriage. Exceptions -
1. I knew two LTCs at Fort Benning in the late 1980s who had managed to generally be assigned together or at least in the same region throughout their career.
2. I knew one 4-sat general whose spouse retired as Colonel
Since the majority of those serving are still men it is not surprising that the male divorce rate is generally unchanged
There are fewer women than men in the Army and many are probably married to people not currently serving. PCS, TDY, deployments add stress to any marriage. I am not surprised that there is different rate between the genders.

I don't understand your assumption. If all married service members were married to other service members, then you would expect it to be the same, but that's not the case.

I think wives are more apt to follow their Service spouse around the various postings of a career, more willing to constantly relocate than husbands of female service members. Most family programs and spousal support groups are tailored to wives and the husbands feel like the odd man out, literally.