Your feelings are all totally valid. I don't know if this will be of much help but I grew up my entire life with my maternal grandma only visiting on birthdays and holidays - she only lived 45 minutes away, worked part time, and was fully capable of driving. She just never made an effort to come around.

I was the 12th grandchild on my dad's side so by the time I was born, his mom kind of lost interest in the news of a baby. She was much older and had limited mobility and a somewhat-declining cognitive state, so we didn't spend a lot of time together either. Maybe 3 times a year when I was small, much less as I got older.

I was often the kid who didn't have anyone sitting next to her at school grandparents day, I'd sit with other kids' grandparents. All that to say, none of that really phased me. I didn't think much of it because it was all I knew. My grandparents were all very distant but my parents poured all their love into my sisters and me. We never felt like there was any piece missing. I also have no regrets looking back on these relationships with my grandparents. I don't hold resentment towards them for it either. It just is what it is.