Bummer about the dairy...cheese and all its relatives are handy for low-carb cooking. However...

Avocados!
Mayonnaise (avocado or olive oil types)
Coconut oil
Bacon, bacon, bacon

Lots of delicious fats can make cooking fun again.

All those commercial snack bars are trash, so you're well rid of them. However, you might investigate recipes for making your own, with better ingredients and no icky fillers.

Sorry about the hospital. Please stay out.