Your email account *should* be terminated once you leave the service.
That usally happens when you out process, before your DD-214 goes into effect.
As far as the Navy and Marines go, with NMCI, your email account is *supposed to* follow you around as long as you are still on active military duty with a command that has a UIC.
Once you transfer from a command your email account is not shut off, you just don't have a UIC that your account can be attached to.
Some command computer geeks will not delete your account from the commands UIC so your account will still be active when you transfer.
Two years TheRedHorseman? Where do you check your email from?
What branch of the service?
I used to be able to check my local .mil email account from home, once it changed over to NMCI that went away.