I'm glad things went OK. From the sounds of things your Mother didn't freak out, which is a plus, however, the whole "lets go see a therapist" thing suggests to me that she is either uncertain or somewhat unaccepting. Usually when someone refers you to therapy over something like this, they are doing so under the pretense that this is an unhealthy behaviour that merits changing. I definitely would not see a therapist if your Mother is selecting them, that could cause strain between the two of you and thrust you into conflict with your AB/Little side as well
Then again, there's always a chance this could backfire for your Mother as most therapists are knowledgeable about fetishes and alternative lifestyles and take a rather lax and accepting approach. Perhaps you could even meet your Mother halfway. I do know that there are kink and alternative lifestyle friendly therapists out there, perhaps you could select a therapist like that
I know and have known of some ABs who are/were in the military as well, this isn't something that caused conflict within their profession, the same should hold true for you as long as you keep this private, discrete and to yourself
I certainly wouldn't tell any of your military cohorts
For now, take things as they come and see what your Mother has to say when you two talk further. If she presses you to consult a therapist, choose one yourself. It's hard to say what progress if any was made here, this sounds like a one step forward two-steps back sort of an exchange. She didn't get angry and has reinforced her love for you, but the mention of a therapist suggests that she has some sort of misgiving regarding your newfound stress relief