mother in law from hell

So my mother in law has never liked me, no reason, just the fact I took her only son away! I find her so selfish and self-centred and rude! And she really is! So we want for our first on Tuesday , it was amazing to see our baby 😍 so we called my dad and sisters to tell them and my best friend and my husband family , I didn't want her to no but you can't leave her so so we called and she said you did call me first! Didn't you! So my husband said yes (we didn't) but want differents dose it make? Follow by you must name the baby after your grandad ! (No) so put the phone done and left it at that. 
The next day I'm at work bored and looked on Facebook only to find she had posted the scan of our baby with the caption I'm going to be a Nan isn't this great for me! Like what the hell! I haven't announced our new yet! Only my direct family no! I haven't told my work! Why would you thinks it's ok to tell the world my news! Why would you think it's ok to shear my baby with the world 🌎! And why would you think it's your right to do this! I haven't posted any think, and I'm not ready to share my precious news yet! She didn't ask us she just did it to compete with her cousins and best friend who's son is also having a baby! This made me so mad 😡! I mean am I wrong to be so angry? I know you guys don't no her but she has really pissed me off! And my husband called her she didn't answer so he text her, she text back 5hours later ok and she took it down but I'm so upset over this x sorry for going on x but I'm still venting x