Hi there,Boy, I can relate to this in a way, I have experienced that with my in-laws and own family.
I have observed, that it is not just me that they do this to, so I do not feel any longer it is directed to me.
I do see it is their rudeness and ignorance, not mine so I limit my time with such people or even have declined being in their gatherings. I do not know if you are able to do the same or try this manner of dealing with them, being that I do not know your family,in-laws and your relationship.
I know it annoys me when we travel hors to visit them (holidays) I just cringe, and hope not to let it upset me too much, I think I have gotten use to it.
Another thing is when I have mentioned it to my husband he claims he doesn't notice it as well as not noticing that they making fun of my ancestory, they do not like other nationalities but their own.
The best is to try to distance yourself to these sort of folks.
I wish you the best with this, cause I know for the longest time I kept thinking I was boring them, or their conversations were more important, then I stopped myself from thinking that way, after all I do socialize verbally, make small talk in the public and many people talk to me, so I no longer take any of my in-laws or relatives rudeness and ignorance to heart, I hope in time you will develop this approach as I have, it takes awhile but will get easier in time.

Take care and have a good new year

DE