my mom is controlling af

My boyfriend got me this ring for our 6 month anniversary yesterday and I posted this on Instagram and my mom got super mad and just stormed in my room and made me delete the post...? She's like "cmon think, that's not all you should be focusing on". Mind you I'm almost 19 years old and I'm in college. I still live with my parents and go to school so I guess she has a say in what I do. She says she likes my boyfriend and stuff so idk what her deal is. She stormed in my room freaking out saying to delete it cuz it loooked really bad I'm only focusing on my relationship. How can I even deal with this??? I think my mom is mad cuz I don't have a lot of friends rn becahse all my high school friends have cut me off. But it's not my fault! How do I handle this? And do you Think posting this was bad in any way ?