The sad fact is our families can be hard on us – and on our spouses. Be ready to run interference, support her, defend her, or say “ENOUGH!” if it comes to that. Do this with both her family and your family.
The best way to do this is to talk with her ahead of time so you have a good idea who gets to her and how. Also, get her to tell you what does not bother her. Come up with a signal she can use to let you know when she needs help. If someone has a habit of going at her when they get her alone, don’t let them get her alone.
I know it’s horrible that this can be needed, but it’s a common reality. Step up and protect her. Aside from being the right thing to do, it will earn you some major hubby points.