When your children grow up, and believe me, they will - Mothers Day is like waiting for something to happen. Only it never does. Of course, it depends on the ages of your adult children.
From about age 18 till 30 - Most of them, are having a blast - living on their own and while they love their Mothers, they don't usually plan ahead. So you tend to get a Mothers Day phone call at like 8pm in the evening, or a card 2 days later. You sometimes, get a lot of excuses and platitudes, "Everyday is Mothers day" etc. It's okay. I don't mind.
I've done the same thing when I was younger and my Mom was a bit more picky than I am - she chose to take it personal - which I do not. I find, when you EXPECT something, you WILL get hurt.
Then when the children are having their own children, they still put you on the back burner. Or they have to share Mothers Day with the Mother-in-law too. Or they agree to put both Mothers on the back-burner and use the excuse that they are now, busy mothers or a busy Dad with children and have things to do. It's okay. I don't mind.
I did that, too. My mother would put on a grudge, that lasted through summer.
It's not until, your Mother gets old, that all of a sudden it kicks in - that you may not have much more time with her and so you try to get in, as many as you missed. I am sure these older Moms appreciate it, but after like age 80+, many of them, just don't care anymore. And would be just as happy with a card or a phone call. Maybe they would rather just sleep or watch reruns of I Love Lucy.
My mom is gone now - since 2008. I was always in trouble for missing Mothers Day or being late. I had no excuse other than - I was always too busy.
It's okay. It's all good now. My sister and I are no longer in trouble.