While I am somewhat of a proponent of online schooling in general, I must agree wholeheartedly with the overall theme of the other posters so far: if you attempt to go the online route you are risking a very low upside with a HUGE potential downside. However, I would like to provide an alternative to think about.
While it might still be very hard, brick and mortar schooling isn't automatically a non-option for you. As someone who is applying with a family and looking at a long distance move, my wife and I have realized there is a chance she will need to remain behind for a year or two before moving to wherever I'm going to school. While this isn't ideal by any means, we have both realized it can still physically be done. Maybe you should consider flipping my concept and seeing if your spouse would accept a situation where when the next move occurs you simply stay in place for the last couple or few years to finish up. Like many of the other posters have stated, you have to weigh out your desire for the PhD against the challenges facing you and make your own decision on your future. However, while I will still say it is your decision, I will repeat that the online option has an incredibly small chance of getting you what you want, unless you wish to simply have the name of Dr. in front and have no desire to actually ever practice in the field in any capacity. At the end of an online program you will have racked up tens of thousands of dollars in debt, be receiving a degree from an organization that the vast majority of internship sites (let alone employers) will not accept, and will have received substandard training which does not prepare you for the work you wish to do.
If you truly want to, and with the proper support from your spouse (remember, as a military spouse there are likely a ton of sacrifices you've made for him/her, maybe it's time the sacrificing went in favor of you), you can most certainly do this. But, take the time to make an informed, logical decision and get creative with how you're going to handle it. Good luck, and I wish you all the best!