I'm childless and do not understand this view nowadays that DH/DPs are expected to buy gifts and pander to their other halves on Mothers Day. The women aren't their mothers.
The day originated from Mothering Sunday when all the girls in service were given a day's holiday to go and spend the day with their mothers. There's no record of the mothers being pissed off because their husbands didn't buy them something.
As a child in the 40s and 50s I don't recall my DF buying my DM anything - his focus was on his own mother and when we were old enough we would make a card and buy some flowers for DM, make her breakfast in bed etc.
When did it all change?