Good ideas here. I have been dairy-free for 18 years. I think it's cheaper. Bake with water instead of milk (add a pinch of baking soda if it isn't quite right).
For sauces, try coconut milk or a small amount of arrowroot as a thickener. Some people use cornstarch or tapioca with good success.
When making soup, put a portion of it in the blender, then add it back into the soup for creaminess - or cream up the whole soup (mushroom?) and use in casseroles. Or if you have a hand-held blender stick, put it right in the soup pot and cream up a bit.
Silken tofu adds creaminess to smoothies and other things.
I like Earth Balance margarine, though it's not cheap - there are cheaper margarines, of course.
If you crave cheese, try hummus, Soy Boy tofu-lin, or fermented foods.
There are some good dairy-free ice creams for treats - can be used instead of whipped cream with shortcake, etc.
In frying, use oil or pan drippings (bacon fat!) instead of butter.
You'll get used to it. Seriously, I think your budget will shrink a bit. Dairy is expensive.
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