Personally, I would ditch the chewing gum entirely and permanently. It only keeps your tastebuds in sweet stuff mode. You want to re-educate them.
About dairy, it can be a very helpful part of a ketogenic diet as long as you go for the options that are higher in fat relative to milk solids. Some of my favorites are cream, cream cheese, mascarpone cheese, brie, camembert, and such. I don't drink just straight milk because the lactose to fat tradeoff just isn't good enough.
But any dairy product is ok as long as you are figuring those fat grams vs. carbs and coming out ahead for the day.
Another non dairy option is cultured coconut milk. Tastes like kefir only better. Yumm.