Nasty daughter in-law

I'm now at my witts end for years I've been helpful,polite and kind despite my daughter in-law. But the past 12 months she's stepped up to another level trying to split the family up she's particularly nasty to my daughter who has tried to be friends. She's now latched onto my other daughter in-law and doesn't leave her alone. Christmas day we visited each of our sons and family but had Christmas lunch at our daughters who invited us first .my older son and wife were lovely but on arriving at other sons his wife didn't speak to us and ignored us .im so mad I think there no need for rudeness .she didn't even say bye .so now I'm left wanting to pull her up over it .The only reason I haven't said anything is because of my grandchildren .