Alan if you're near Dublin, there is an indoor skiing place in Sandyford where it's a white astroturf laid over a very wide travellator type floor - actually great fun! Or there's the outdoor artificial ski slope in Kilternan (we haven't tried that one).
Would you get out into the mountains or a national park or forest somewhere within a reasonable distance for a family walk? Looking for animal tracks, or signs of what nature is doing in winter, practicing map reading, challenging each other about "will we make it up to that rocky spot?" etc. Could be nice to find a good coffee shop or pub towards the end of the walk (shortly before the end or not long in the car to get there after) for a hot drink and maybe a treat - even if watching weight, a good walk allows some extra calories to be consumed.
For breakfasts, while a full Irish might be a bit much, there are other options that are not so calorific but good to sit around. Fluffy scrambled eggs with smoked salmon (or bacon) and cherry tomatoes on toast is still filling but not as bad as all the meat. Or proper juice and a bowl of fruit salad (can make that the night before) and a cafetiere of coffee. Or pancakes with a choice of bacon, maple syrup, Nutella, or berries.
I like the idea of heating DH's coat. And trying to corral the DC "crazy" so the house is calm and welcoming when DH gets home - I know that the clutter and chaos really annoys DH in our house (whereas I walk through, drop things as I go, and start into making dinner).
If babysitting is tricky, and it is a good time of year to find local teens looking for babysitting jobs, could you do "date night" at home? DCs eat early, and either are put to bed on time/slightly early, or older DCs are "persuaded" (perhaps bribed) to head to their rooms quietly (watch something on Netflix on a tablet? given a new book/comic they will be absorbed by? 2 allowed to play a quiet game together without interfering smaller DCs?) - allowing you and DH to enjoy a relaxed dinner together downstairs. Set the table nicely, use side lamps/candles, and while not necessarily dress like going to a ball - wear something comfortable and nice and a little bit dressed up.
Are there little things you could do for DH, like putting a festive treat in the car/coat pocket for his commute, making sure the tank is filled with petrol to save him a trip, picking up a favourite beer/wine/gingerbeer/non alcoholic drink to have with dinner one night (or a Christmas/Winter beer if he would try it? Deveneys in Dundrum have a good selection usually, but others will have some options).
The only place I know for sure that does small packets of coffee beans (and will grind them if you want) is Mahers in Cork city. But there is a coffee place in Dun Laoghaire that I keep meaning to try and they look like they might do similar.
On bad weather days, especially if DH has to commute even part way on public transport (which is miserable in winter!), could you pop a pair of reusable hand warmers in his pockets/gloves? You click them to heat them up, and then boil them for about 10 minutes to recharge them afterwards (I usually do ours in a seperate pot when boiling pasta as they take about the same amount of time).
And have dry (and warm on radiator?) socks ready when he gets in on wet miserable evenings to change.
Going to try to take some of my own advice now and do a few more things for DH....