Hi,

It is really stressful, isn't it? It always surprises me that so many advise to give a bottle once a week (or whatever) from early on so "they learn to take a bottle" In my experience they really want the boob - and may at any given time just refuse the bottle!
But, she will be fine. Calm perseverance is the key here! Who is caring for Mia while you are at work? Are they calmly and patiently trying to give her a bottle while you are at work? How many days per week/hours per day are you working? Have you made arrangements to pump for her.
Try....walking around the garden with her while you try to give her her bottle, destract her, make feeding into a game.....slip her off the boob at night when she is pretty much asleep and slip the bottle in. Act as though you really don't care if she has it or not, but she is missing out on a lot of FUN. Make sure the bottle top isn't screwed on too tight - this will impede flow.
Once she gets the hang of it you'll wonder why you worried so much
Regards
Barb