The Servicemember's Civil Relief Act allows military tenants to break their leases when their military orders require them to move, e.g. to a new duty station. However, state laws can and do impact that ability. For example, if you live in Norfolk, you couldn't break your lease if you were PCS'ing from Little Creek to Naval Station Norfolk. But, if you were going from Dam Neck to Yorktown, it might be possible. Further, in Virginia, your security deposit is pro rated over the length of the first year.
I HIGHLY recommend that you talk with a JAG to break the lease properly. Just because you can do it by law, doesnt mean that the landlord will follow the law and will be hell until you have a court prove you right and force the landlord to comply