Mother's Day is just a massive con, invented so that card companies can make money. If you have to wait for one day a year to tell your Mum you appreciate her, you're not doing much of a job. I phoned my Mum tonight for a chat - as I do twice a week, without a designated day to tell me to do so. Same goes for father's day. And valentine's day. And people's birthdays. And christmas.
Erm, no. It wasn't invented by the card companies, the Mother's Day tradition goes all of the way back to ancient Greece and has been celebrated in England since the 16th century.
Likewise with the other 'days' and obviously Christmas and birthdays have a lot of history.
You're right that it has been commercialised to fuck though.