I've never worried too much about hidden dairy in my diet, although I've been pretty careful about it in x's, but I have been dairy-free for over a year now too and I feel your pain! I have been wondering when I could start having dairy again, and earlier this week I had some chocolate biscuits - x was up screaming for 2 nights (and started one of those days at 3.20...) and apart from that has sttn for the last 2 weeks. I'm inclined to think that it must be linked so I am holding off again for the time being.
We didn't realise that e was mpi until she was 18 months, and she didn't get dairy until about 2.5 - I figure that actually I am going to wean x long before he is able to tolerate dairy on his own.
In the mean time, I can get away with dark chocolate (there are quite a few which don't have any dairy products at all and others which don't seem to bother x), and sheeps cheese (manchego and Roquefort are reasonable substitutes for the time being). I haven't found an ice cream substitute though, and I really miss it.