I Dislike Being Told to Calm Down

I am somewhat private and keep a whole lot of stuff inside so, occasionally I will get mad and go on a rant. After writing something, usually metaphorical, which helps me to get it off my chest I get told to get off the internet or that I need to calm down. I don't friends have that I can vent it out to in small doses so eventually it builds up and comes out. Rarely do I actually vent verbally except maybe a few times to my mom when she pried it out of me, even then I won't say everything I am thinking, and she tells me I need to go calm down. I usually do it in writting, if you don't like it, don't read it. There is so much hatred and anger in the world and sometimes all I need to do is vent about. I don't really have other methods to vent it. Ugh