MREs are required to be shelf stable for at least 20 years. They want to be able to have warehouses full of them waiting for if they ever need them.I looked it up and it was discontinued like a decade ago so unless they've brought them back someone eating them could get really sick and be hospitalized. I know they last well past the expiration but 10+ years is kinda pushing it.
Pretty sure she was saying thanks for supporting her over the past 3 years, not that that was how long she'd be gone for.3 years? So either contract work either government or construction or some shit. Or College related (post graduate studies) or she's pregnant and wants to take 3 years to raise the kid.