My advice is to not even think about making only a partial change. You may
be shocked when you eventually discover what a tiny amount of milk in
someone's diet can do to them.
I don't want to go into details, but my personal experience tells me that a
"partial" diet is no diet at all, and that it is not the end of the world to
have to change your cooking habits. You will get used to the new ways after
a few months and it won't bother you any more.
With love,
Patty (San Francisco)