Posting pregnancy announcements on Facebook. Harmless or heartless?

im a believer in sharing what you want to. this is an exciting time in one's life and im all for it! But after ttc for over 2 years and seeing people's announcements, it makes me upset. i know that sounds terrible but its made me think. when i do someday find out im pregnant, i think ill just tell my family and close friends and not post pics about it or pics of my baby. I know how hard it was for me to constantly be reminded all of the time, so i dont want to make another woman feel sad.plus why do people who I dont speak to on the regular need to know? if there was no social media, nobody would know anyway.