First bottle

How can I tell my freaking boyfriend that he needs to be the first one to give her a bottle so she knows she can get food from others and not just me?!? I can only argue it with him so many ways. His reply is “she will be more likely to take a bottle from you since she already associates you with food.” I keep trying to tell him that the whole point of giving a bottle is so I can get a break and she learns that others can give her food too.