That's an interesting way to word your dialogue.
To the point though, if you're in the military and you've got an "LDR" (I don't consider them actual relationships as any intimacy is nuanced at best and nonexistent as anything second to best.) it's a lot easier to be a troop, NCO or heck even a commissioned officer without being in a long term, let alone long distance relationship. Introducing an LTR in that lifestyle is tough on everyone and should NEVER be taken lightly.
I can count on one hand military men who have never been divorced to my knowledge. Unless you plan to serve 20+ years and retire, I'd stay away from marriage or having children. It's really lonely for sure and being around that much testosterone can really make you go nuts at times. However, dealing with the stress of cheating, divorce while being in the service (The service, despite being mostly male is NOT something that means the divorce courts will be forgiving. It's actually the opposite.) is the sword of Damocles! That kind of worry, stress and distraction can really blunt your focus on missions or individual readiness and fitness for duty.
I'm not going to say you're right or wrong for what you said. Although I also don't blame her for what she said. Civilians won't ever really understand 100%. Especially a love interest. My own mother called me crazy just for joining up period. My dad said I was crazy just for picking the Marines instead of another branch, but he "Had a gut feeling" and knew I was going to go into the military.
I've been ready and fully qualified to die since July 28th 2006 but I'm still here. A lot of us aren't. That's something everyone knows to some degree about military personnel. Be glad that came up before you decided to move her on base or something. I'm not telling you what to do. I'm just telling you what I've seen and given you my opinion/advice. Stay alert and best of luck for your pursuit of joining an elite unit.