If you Google bipolar rage you will see it is quite a recognised thing. I found the Cbt for dummies book, and the Cbt workbook for dummies really useful for this. In addition, I usually can't control my rage when my meds need a tweak .
I also find my rage to be particularly bad when I am struggling with hormone changes which at your age you might be. Do you use a mood tracker which can also track your period? You may find that helpful.

Good luck! Life at eighteen can be hard enough without the added stuff that bipolar brings.

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