I really feel you on this, it is such a hard place to be in and your love for her comes through in every word you wrote. My girl was the same way at that age, and what helped us was having my husband try the bottle when I was completely out of the house, because babies can smell mum nearby and will just hold out for the real thing. Some mums in my circle also found that switching to a soft spout cup or even a straw sippy worked better than a bottle at this stage, so it might be worth trying that before you go back to office lah.