Baby Mama and Family

I know this might sound weird but i need to know if anyone is in the same boat as me. We have 2kids with my hubby each from previous relationships, so my SO's ex picks both our kids to stay over at her place for the holidays(wondering if thats ok) the son also comes over to our place from time to time, is this ok? Lately the ex and SO talk about everything all the time and it kinda gets me on edge, is it ok for me to feel this way?