What we generally do is keep the juice out of the house. Juice increases the risk of cavaties, and even 100% fruit juice is loaded with extra sugar and calories. At a seminar I went to on child nutrition (I do home day care for a living, so have been to several), the speaker made a good point that 3 oranges might go into a glass of orange juice, but one is not likely to sit down and eat 3 oranges at once, so it just encourages a less balanced diet with those extra sugars and calories at once and the whole fruits offer more nutrition and the fibers and such so better to eat the fruit and drink the water instead of putting it together in juice. Also, I've known many kids who stop enjoying water after getting used to juice (main reason I've limited juice being in the house from the beginning because I knew this could happen easily enough...my older son had juice first as a potty incentive...tasted yummy as a treat and gave him ammunition to go, so it was our potty treat and then I stopped buying it again). So what I would do is eliminate the availability of juice, so it's not even in the house and with milk, have a glass at each meal time with the food. If still thirsty after the milk, water and water between meals. This will allow for the appetite to have a chance to get hungry. It is your job is to provide the nutrition, it is her responsibility to then consume what she wants from what is available :)
All that being said, a son of mine has sensory integration/processing disorder. Food has ALWAYS been a challenge for him since he is a sensory avoider. We've finally gotten used to a good system that really helps tremendously with him now that we've gotten to the point that he'll come in the same ROOM as foods that are not ok with him (by look, texture, color or what not). We have a box with food labels and pictures of foods that are okay by him to eat and acceptable by me for him to eat for nutrition, so he can choose something from that box if we are having things that repulse him. He's begun to be a little more open to trying new things and we get excited to add a new food to the box of his foods. So, if it IS a sensory issue, slow steps in the right direction work and I could share more ideas with you on that if you are interested.
Best wishes to you!