My husband is active duty and his home of record is in a different state than we lived in 2015. Do we need to file separately?

What was your husband's state of legal residence and what was you state of legal residence (not where you were stationed together, but where you came from to be with your husband)? Also, where were your stationed and did you earn income there?

My husband's was florida,and mine was Oklahoma. I moved to Virginia with him and  became a resident and worked in Virginia  as well. His orders are to Virginia.
Thank you

And he is still a FL resident, correct?

And was there a reason you changed residency to Virginia, rather than stay a resident of Oklahoma?

Yes he is, that is his home of record. I changed it to live with him in his duty station

What did you do to "change your residency"? VA Driver's license, register to vote?

Your husband's state of legal residence is FL and he is exempt from VA tax on his military income while stationed in VA.

As the spouse of an active-duty military member, your state of legal residence does not have to change just because you are accompanying your husband to VA as a result of his assignment. In many cases, you can even be exempt from VA state income tax on your VA income.

To be exempt from VA state income tax on your VA income, however, VA requires you and your husband have to be residents of the same state. In your situation, that is not the case.

Now it gets a bit tricky. If you are still an OK resident, you and your husband can file a joint, non-resident VA tax return. You will still pay tax on your VA income, but he will not pay tax on his military income. 

If, however, you are a VA resident , you will file a joint federal return with your husband and you will each have to file a separate VA return. You must file on Form 760, he must file Form 763. 

This is hard to do using TurboTax online. It is much easier to do using a CD/Download of TurboTax. 

https://ttlc.intuit.com/replies/3301995

Here are some articles that provide additional information on how state taxes apply to military members and military spouses.

Filing State Income Tax When You're in the Military.

Military Spouses and State Taxes