Nadine, sounds like she's out there in not-coping-land. As a temp single mummy I understand all too well the aggravation that an absent partner causes (which I believe is quite different from just flying solo all the time). For starters, the uncertainty of her DH's return date is the sort of thing that can quite literally send you around the twist. Especially if she resents him going in the first place (it sounds as if the whole trip is an exercise in disempowerment for her. It's hard to understand how deeply that can affect you unless you've been there yourself). Add to that the stresses of managing the relationship with the absent DH and you've got multiple layers of stress on top of the rigours of suddenly finding herself a single parent.

As to her fears at night, that sounds to me like she is having problems managing not only her stress but her anxiety levels as well. A feature of anxiety disorders is overreaction to threats that don't exist. I suspect she's wearing her "No I'm fine everything is ok" mask at work (where it would be especially difficult to admit to the problems she is having). I love your suggestion of just popping in and hanging out and being supportive, she probably needs this more than anything else. If the topic of her stress/anxiety/feeling overwhelmed comes up, maybe encourage her to get some counselling, so that she can find some strategies herself.

I think you're lovely for looking out for her like that. The world needs more of this!