If they're feeding constantly she'll be sore, irritated and tired - I can't blame her for wanting to get away
I don't think she's rejecting them, just trying to get a bit of space maybe ?
If they've all fed, you could try keeping them back from her for a bit - but obviously if they start squeeling and she gets distressed it might not work.
Does her milk supply look as if it's getting low ? Any severe swelling or redness to any of her teats ? It might just be painfull for her and that's why she's moving
Short of going for the stresnil option (which I think you might need to consider if she keeps going like this) I'm running out of ideas
so trying to get hold of OH @ work to see if he has any suggestions (he worked at a commercial piggery many moons ago and delt with lots of farrowings) I'll post as soon as I get hold of him, if he's anything further to suggest.
I wish I could help more Helen, sorry