How do you stay calm when things don't go your way or yo in get into an argument?

I'm nearly 35 and often feel like a child having a tantrum. It's horrible. If I don't get my way I get mad at my partner, call him names, tell him I hate him and that I no longer want to be with him. I shout and cry. It's embarrassing.

I just don't have a filter. I can't stop the upset and anger and the words from just falling out of my mouth.

Please help, I don't know why I'm like this and I want to change