I was 46 was D18 graduated, DH 44 and my youngest will graduate 2021. I will never forget when I went into D18’s 1st grade class and it was my birthday. The kids were guessing how old I was- all the ages were in the 40s- I thought, how old do I look!!! Turns out I was just a lot younger than their parents, they were saying their ages! A lot of our friends with kids are closer to my parents age than they are to me. You can tell there was a major culture shift between early Boomers- my parents and late ones- my friends.
I often say there is your age and then there is your “mom” age- that’s how old your kids are, you have a lot in common with your “mom” age friends as your kids grow up no matter what your actual age is.