Hugs..at the end of the day it doesn't matter how your baby gets fed, as long as they are fed. I still feel guilty about T but then it remind myself no one was happy when I bf him, not him, not me, not DH not Z. so how was it best for him YK?
There is no reason you couldn't maybe mix feed? If your everything free, you could see if a few bf a day are ok for him? Then if he can tolerate your milk increase back up to drop the formula?