Yes exactly! IDGAF if it's petty and pathetic. If someone CBA to even give me a birthday card, or gift, then they'd ain't getting anything for theirs.
Ditto Christmas cards. I will send one to someone, once, and if I don't get one back, they get no more. Why the hell should I be buying and giving to someone who CBA to give me a second thought? Fortunately my 2 DC have always got me something (and DH.) And they never need reminding. And we give to them of course....
One of my cousins (same age as me with DC a similar age to mine,) was an absolute monster for this. I have 2 DC and she has 4 (10 years between the youngest and the oldest,) and I used to buy all 4 of hers gifts for Christmas, and all the birthdays too. Well, I did for 4-5 years then I stopped. First couple of times my DC got second hand toys her kids were done with, and second hand dresses and tops that stunk of cigarette smoke and had stains on them..... I just binned the clothes. I was so disgusted. After the first couple of times she stopped giving. I carried on for a further 2-3 years, then thought 'fuck it! She CBA with my DC.'
My aunt AND my mother said she was very hurt that I had stopped. I said 'she doesn't give my 2 anything!' Then I got a sob story about how she was really poor, as she was on benefits and had no surplus cash. Whereas DH and I were loaded as we both work. (We weren't!)
My cousin managed to afford a pack of 20 cigarettes a day though, and to have a new tattoo every 2-3 months, and go to Ibiza 2-3 times a year with her mates. Also bought a Playstation 3 for her 2 sons - one each. Just after they were released... £400 each at the time (this was 2006, so that's like £700 in today's money! And she bought two!
Couldn't afford a couple of 99 pence selection boxes for my 2 DC though.
And I was meant to feel guilty for stopping buying for her 4 kids... 
I didn't!