I think the real story here isn’t the Major’s sexuality, but the how her command came to decision to file discharge paperwork, especially with about two years to go for retirement.
I am especially curious how this issue came to the attention of the Air Force since it sounds as though she kept her affairs at home and didn't "tell."
So not only did she not violate the don't tell part of the policy, the Air Force itself violated the "don't ask" part.