Sadly, not alot you can do if she is able to get to the pigs.... that is the only good thing about the farrowing crates, they cannot turn around and get to the piglets.
Does she have mastitis? If she is being aggressive. I am not sure how you will check her unless you can get her into like a chute of some sort where she cannot turn around enough for you to be able to check her udder.
A shot of OXYTOCIN will help with milk let down if for some reason she is not letting her milk down... it will also help if she has alot of swelling because it will ease the milk let down which will ease the pressure which will help ease the swelling a bit.... Dexamethasone will help with swelling but it will hinder milk production some so you have to be very careful of using it....it can cause abortion too.
Take the pigs away for an hour or two.... give her a shot of oxy..... put the pigs with her if she is laying down.... Takes a couple of minutes for the oxy to work if you give it in the muscle... takes a minute when we give it to a cow in the milk vein...
If she is really bad, call the vet. They might give you something like rompum.... which is like a sedative.... relaxes a cow to the point of almost laying down if given too much... might calm her enough to get the pigs on her sucking so that when she "comes around" she is accepting. It is short acting time wise. We will use it on a cow if needed to work on them.... up and going in less than an hour at most.... have used it on really difficult dairy heifers in the past.... and they are nearly back to normal in 15 minutes.... VERY SMALL DOSES needed.
BE VERY CAREFUL OF A SOW THAT IS BEING AGGRESSIVE/SAVAGE. If she turns on you , you don't have a prayer to get away from her.... Just USE CAUTION