Am I overthinking??

So my mother inlaw only sends birthday cards/gifts AND Christmas gifts to him. Never me, never a shared gift, ever. Is this wrong? I feel some type of way over it, as if it's just wrong and rude. She doesn't even wish me a happy birthday yet he gets the works. Been with him for years. Thought maybe once we married she'd then change but nope!
I cook for her. Make her treats. Pump her up like rebox, send her Christmas cards, gifts and treats. She's very nice to me in general, I just don't get how she's wired.