‘It’s a waste of money’: Entitled "girlfriend-in-law" doesn't make any effort to get to know the family of her children's father, so “sister-in-law” removes her from the holiday gift list

Family dynamics can be funny, especially during the holidays. Take this sister's "girlfriend-in-law." The brother has an on-again/off-again girlfriend that he has two kids with. We don't know the relationship between the two other than it looks very toxic, hence the on-again/off-again. So, this coldness also comes out in how she treats the family of her children's father. She acts entitled, but also closed off. She only wants to hang with them when it is convenient to her and will get in loud shouting matches if anyone disagrees with her. The family loves the children, but it is hard to spend time with them without her. So they endure it.

However, this coming holiday, the unofficial "sister-in-law" decided to take a stand. She now refuses to get this "girlfriend-in-law" anything for the holidays. True, it is half because she straight up just does not like her. However, it is also because any time they have gotten each other gifts before, it's something the other doesn't want at all. So they both just end up getting each other junk. To save herself the space bother physically in her home, but also in her mind, she's not giving a gift and not asking for one. Is this how you would handle your strange family dynamics during the holidays?