My ex girlfriend is intollerant to lactose, less so now, was very badly intollerant a little while ago. But yeah, when i was with her, my dairy intake dropped a surprising amount :P
She drank Rice Dream, but not very often, didn't really need to use milk all that often - no cereals or anything like that due to being intollerant to gluten also :S.
But yeah, not as hard as it would seem. You may miss cheese (i would :<) and chocolate, but as stated, there are other means.
And learn to love black coffee and herbal teas. Never used to drink either of them, now i can't have my coffee any other way and love herbal teas so, so very much - here we have a lovely moroccan mint tea by dilmah, damn good. Miso soup is great too
I'd really miss camembert cheese :<