I just went back to work today. We have tried different bottles and nipples. We have tried having someone else feed him while I go for a walk. We have tried daddy feeding him facing outward, cupping his chin.
Nothing seems to work.
I only worked three hours today so that I could run to the babysitter and feed him. You have been doing many of the right things to help your son learn to accept an alternative to breastfeeding. Breast milk in the bottle would smell and taste much more familiar. Be sure some breast milk is covering the outside of the bottle nipple so that he gets a good taste of your milk right away. Some bottles flow much faster than the breast, and breastfed babies may feel they are choking when the bottle flows so quickly.