Where has time gone??

Last week I put my baby girl on the bus for the first time. I rode to work alone for the first time in years (except those days when everyone is sick and home but I am sick and on my way to work! lol) And she didn't even cry. But I did a little. I cannot believe she is in school, she is 4 years old, and she does not miss me once during the day. This is the same little peanut who would FIGHT to get to me the second she heard my voice. She is attached to me always and just seems very content about it. BUT in school... now... she is queen bee! I love it and loathe it at the same time! I am so happy she is happy and smart and healthy but I just wish I could keep her small a while longer.
Same goes for her big brother! He seems to outgrow me faster and faster everyday! He is such a big boy but really needs to defined my boundaries a little better for me! He wants me to stop in his class but I cannot talk to or touch him. He wants me to help him or say hi at lunch but I cannot kid with him or his friends. He is so funny!! It is crazy to see them both forming their own social identities and figuring it all out.
So... here I sit on the eve of my birthday... my babies are growing... and in a month I will have my 20th class reunion. RIDICULOUS!! Where did time go? I feel like I have done everything I wanted to... is that sad or what?? Where do I go now?? I am still that crazy chick from college... I am still the cool aunt, and I am still learning a ton everyday in my career... so then why is it that I feel so melacholy when I do the math and realize how much time has passed? That the bag boy at the grocery store calls me ma'am.... that the kids who were in my first Kindergarten class will graduate in 2 years and the first kids I taught have ALREADY GRADUATED!!! what?? Again I say ridiculous!!
This post was not meant to lament about times gone by. I do not wish to go back and change a thing... I do not regret a single moment of my life... I just can't believe how much time has passed... and how many more good times there are to have!!