Lol...isn't there a Womans Day? I don't really get the gist of your argument. What you want is already celebrated so why not give the Mothers their day? And yes...it's all marketing and people that have a healthy relationship with their parents, celebrate them and thank them throughout the year. You can't have a holiday that pleases all people, much the way you can't write an article that won't upset anybody. Christmas doesn't appeal to the world. Neither does Easter. Or Ramadan or Hanukah. And neither should a generic day given over to Mums have mass appeal.
To take it a step further. Holocaust Remembrance Day doesn't have mass appeal. UK doesn't celebrate ANZAC Day. Half the world doesn't stop for a minute to think about VE Day and the veterans that fought two world wars.
The point is, it's not great to complain about those that celebrate just because you're different or have had different experiences. Nobody is asking or demanding that of you.