My daughter was allergic to milk until she was 18 months. I ended up nursing her until that time. If you aren't nursing, then soy formulas should be fine, if she isn't allergic to soy. I made sure she got her calcium through other foods, like broccoli, blackstrap molasses, flaxseed, tahini, kale, beans(great northern, navy, black), tofu, soy yogurt, etc. also I had to make sure that she got a lot of fat from her food sources. lots of whole grains and pastas, and tahini, etc.
I would also test her allergy by putting a little yougurt on her face to see if she reacted, then would test her formally in the doctor's office at one year, 15 months, 18 months, etc. just in case we needed an epi pen etc. At her 18 month appt. she did not react.
Most children with a milk allergy will out grow it by age 3, if they do not, then they will most likely have the allergy all their life. If she is only having hives, then she is allergic to the proteins found in milk so she CANNOT have lactaid, etc. You might be able to try goats milk but they have 2 of the same proteins found in cows milk, so you could get lucky and she could be only allergic to the one that isn't in goats milk. (FYI - If they are having diahrrea and no hives then they are allergic to lactose, and can have lactiad or take a supplement to help her break down the lactose whenever they have dairy.
I feel for you. It was very hard to not be able to just give my daughter food whenever we went out - i would always have to ask "was this cooked in butter?" "can i see the ingredients list" and always have to read the labels on whatever i bought. Did you know that some breads have milk in them? ugh. But i just got used to making her food and bringing it with me.
I have a 7 month old now and am waiting to see if he has the milk allergy as well, so I could be right back in your boat in no time. :) I hope this helped and God bless!