I can understand you being upset, but please do realize that even grandparents can be a little absendminded.
My dd turned 6 in November and my mother totally forgot her birthday. Dd was devastated. She was crying because mimi and pop forgot her birthday and didn't send her a card...I said "honey, they didn't forget. I'm sure they'll have something for you when we see them and we'll celebrate your birthday then"
She just looked at me with tears in her eyes and said "but they didn't even call me" sniff sniff
Then, yes, I was angry..really angry. I was angry because my friend's parents are so involved and my parents never come up to visit us, rarely call us etc. They live 2 1/2 hours away and ALWAYS expect us to make the trip down there to visit. I have to pack up three kids and 2 dogs and all our crap and go down there, when we have a lovely place for them to stay up here. At least we could take turns.
Well, I was already a little bitter about that. My kids are their only grandkids. I was very upset that they forgot her birthday.
When I was able to calm down, and after talking to dh, I called my mom the next day and calmly and politely told her that it was Emily's birthday and I TOLD her that dd was upset and crying that she didn't get a phonecall.
I told my mom that it wasn't my intent to make her feel guilty. It was my intent to let her know that we all love them, and don't understand why they don't seem to want to spend time with us.
I told her that my kids are wild about them and didn't understand why mimi and pop wouldn't call them on their birthday.
My mom felt HORRIBLE. She truly did forget. Then she started in with the guilt. "oh I'm such a horrible grandparent..how could I forget." blah blah. I told her to knock it off. A couple of weeks later they came up for dd's Nutcracker performance and we had a little birthday celebration.
A month later it was ds birthday and they were totally on the ball.
At Christmas, oh my gosh, this is just too much. Dh birthday is Jan 9. On Dec 26, mom gave dh a birthday card and a gift. Like, this has NEVER happened that she has EVER remembered his birthday. we don't care about us...it's the kids...but dh was beaming.
I just had to sit down and talk to mom and explain to her that it hurt.
I know they have their own life. They are busy and they are happily married and enjoy their time etc. I don't expect their life to revolve around us..by any stretch! I just told her how I felt, and how my dd felt..and so far it's made a difference.
Nobody's perfect. Heck, our nanny is brazilian and birthdays are *extremely* important..way more than any major holiday. I forgot her birthday in September and felt HORRIBLE. She makes all of our birthday's soooo special for us.
It's ok to feel angry. It's what you do with the anger, I think, that matters. Once you are calmed down and accepting what happened, I think you should just try to think of a non confrontational way to talk to them and let them know how you feel.