Put her in with a bigger hog and let her learn to respect a hog the hard way, or try a muzzle. I think an e-collar will possibly do more harm than good. I had a male the same way n it took a bigger hog to make him back up.
I agree with Charles...a muzzle will eventually teach her to stay clear of the pigs snout...but she will need a vest because it is in her to be rough...