If she started a bragging story about how she disiplined her kids i would probably be all like "omg that's so mean i could never do that, my mother did that to me and we dont speak anymore"

If she complains about her lack of money i would say "thats sounds so horrible, how do you cope, i cant even afford xyz, cant even deal with my bf over one night per week" etc

I would probably also have a friendly conversation about IUD and long term birth control. Not sure where she's founded her assumptions the iud kills you but i guarantee her sources are uneducated.

I'm not advocating this advice this is just how i would react, but my reasoning is it reaffirms your status, sympathises with her (though not really) and turns the attention back on her.