Hey there : ) I feel for you, my son resisted going from formula to milk, too. BUT you have to remember... YOU are the parent and YOU are in charge. And as hard as it may be you need to set the rules, with love and compassion of course, but it does need to be done. She may not like it, and she may throw a fit, but truth of the matter is she will get hungry and she will eat/drink when she needs to. But if you keep giving her the bottle and formula she won't ever go for the food or milk... becuase she knows if she cries enough you'll give in. My son's pediatrician said to go cold turkey, to throw out all the bottles at once. But I had a hard time with that. So I weened him off of the bottles. I gave him a bottle when he woke up in the morning, then 3 meals of food during the day and a bottle at night, before bed. After a week or 2 of that I got rid of the morning bottle and not soon after that the night time bottle. And you know what? He didn't even miss it. In fact, HE was the one who decided he was done with them... one night after only 3 ounces he spit it out and was done. No more bottles.
Now for getting him used to whole milk... I had to slowly introduce it to him. The doctor suggested mixing half and half (formula and milk) and giving it to him in his cup. Eventually, mix less formula and more milk until its all milk. My son wasn't into the cup either, not did he like the milk... he's spit it at me. lol... but after a while he got used to both and now he likes them. You just need to be consistant, as with anything in parenting. Even if they don't like it, repetition will always win over. Just be committed to making the change and do it so that its comfortable for you (like me not throwing out all of the bottles at once). Consistancy is SO important. Be strong and trust that you can do it!! Good luck! I'm a single mom, too, and it IS tough.... but you and I both know that it is SOOOOO worth it : ) You can do this and she will be just fine. She'll adjust to the changes, trust me. She may fight it, but it will happen. We as parents have to do whats best for our children and its not always whats easiest. They won't always be happy with our choices, but we know what's best for them right now. So get a plan/routine going and stick with it. It will pay off. Take care!