Important disclaimer: I know nothing about feeding my baby - yet
I bought this book "Nursing Mother, Working Mother" because I want to BF when this LO is born in 3 months, but I also have to go back to work within 4 weeks of the birth. ( )
Anyway, this book seems really good, (recommended by lactation consultant friend-of-friend over here) and in it they suggest getting someone OTHER than you to offer the bottle (cos you smell of milk and boob and other things he wants) and when offering the bottle, holding him in a completely different way to how you hold him when you bf - for example, sitting on your DH's lap and facing outwards. I think the idea is to establish a sense that bottle and breast are different KINDS of feed, and while he gets the breast from you, he gets fed differently from someone else.
Interestingly, they also say that lots of older babies refuse to feed from anyone but their mum and then clusterfeed/feed all night, and while this isn't ideal for the mum, perhaps, it doesn't harm the baby. I can't remember how old the babies were in their examples, and am too tired to look now, but will try to come back tomorrow (sorry, about to sleep).
Anyway, in case the holding helps - I hope something does! That might not work (they also suggest establishing this within the first 4 weeks so maybe that's a factor) but worth a go, maybe?