I highly recommend that you and another person keep milking the mare and feeding it to the foal. Your little one needs as much colostrum as possible over these first hours........ A regular syringe works in a pinch, but we prefer using a human rubber baby ear syringe for feeding initially. Right now, feed your filly every hour for the first day and then scale back to every 2 hours.
I would also recommend that your vet run an IGg test on your baby, just in case. We bottle fed an orphan from age 2 weeks until he was four months old, although by then he'd been weaned onto pellets too. I really hope, for everyone's sakes you will eventually get your maiden mare to mellow out and accept her baby.
Once you've learned from your vet that the filly has enough antibodies in her system, and it looks like you DO have to continue bottle feeding......you are looking at every 2 hours around the clock! You will also probably find yourself experimenting with different types of bottles (and nipples) until your foal tells you which one she prefers..........But I hope you won't have to worry about that.
Wishing you all the best........
PS: I forgot to mention......if you do end up continuing with the bottle feeding after she's received her colostrum, we had good luck with Foal Lac Powder mixed with warm water, according the instructions. Most feed stores or ranch supply stores carry it.