J.C.
My kids wouldn't take a bottle either. It's actually a very common problem. (It's why almost every other country in the industrialized world allows women to have a year of maternity leave and why kids in our country are sick with things like asthma & diabetes.)
We had to rack up debt to do it, but I ended up not going back to work until my daughter was 12 months, and even then, I made sure I could come home on my lunch hour to nurse. Maybe your friend's babysitter can bring the baby to her work to nurse, or she can go home to the nurse twice a day? I found my mid-day nursing sessions to be relaxing & a great way to bond with my daughter even though I went back to work part time.
If your friend can't work this out, maybe the baby can be spoon fed her milk? In a few months, the baby can some solids & whole-milk yogurt to tide her over.