Hey Mario! Might get to cross paths soon....I work at PAFB and am currently doing work on the radar located there!
I can see your challenge. But it is possible...I manged at Thule for a week once..only had to break out my emergency rations I brought with me on the 1 day there was 0 I would eat for lunch or dinner.
The old 'protein' question...LOL....could retort with 'hmm...I'd ask where you get your cholestoral but that's pretty obvious'.
Might suggest you check out meetup.com as there may well be a vegan meetup group in the area. We discovered this locally about 2 yrs ago and WHAT A FIND!!! Likemind folks, organized potlucks, recipe swaps, also host events for the public like "Plant Strong seminars" as local library open to all, the vegetarians, vegans, the curious.....
Eating on base in the mess is probably going to be the hardest as never can tell without asking or an ingredients card what might have butter or egg, milk, or chicken broth in it. And of course you'll like get just pointed to the salad bar again and again...
If you do your own cooking at home for dinner, suggest cooking up 2x the quantity for leftovers you can take for lunch. I posted some other ideas in another introduction from someone looking for on the road ideas....maybe check that out but if you can't find it I can copy/paste.
Being in the lifestyle for 3 months, good for you. And for your soon to be family. Need to get bit more intell on the nutrition side so you ensure you're getting all the good stuff you need. Lots of good resources out there and books I can recommend.