Advanced boy mom: taking out jealousy of son's girlfriend on daughter instead

I (33F) started noticing my mother blowing up in anger towards me for the small things or even non-issues. This anger is so intense, her tone is and I can see the hatred in her contorted facial expressions, it's completely disproportionate to the situation or whatever I did to set her off.

Eventually, I noticed a pattern. She would do this every time my brother (30M) had a new girlfriend or she heard that he was planning to do something romantic with his gf.

My brother just got engaged to his fiancé, and my mother is getting irritated at me over nothing, trying to start arguments with me, creating problems out of thin air and blaming me for it. In the meantime, she's all-smiles and friendly with my brother's girlfriend.

I think she's a highly evolved version of a boy mum. Most boy mums will direct heir jealousy towards the main competitor, her son's girlfriend, the female who is stealing her "man" away from her. MY mum knows this will only risk losing her son altogether, as the same thing happened to her. Her mother-in-law, my grandma, tried to sow discord between my mum and dad, and that led to my grandma being distanced from the family.

My mother is an advanced boy mum, she knows how to play the game. She's fake nice to her son's girlfriend, then takes out her frustration and jealousy on a convenient punching bag, her daughter, the disposable female.

I'm wondering if anyone else is going through the same thing! I would love to know I'm not alone. Please tell me!