<human>: Hey r/relationships, My 19th birthday is comming up Oct 2, and my girlfriends mothers Bday is October 3rd, and she has decided to do her birthday dinner on the night of my birthday, despite knowing that oct 2 is my 19th birthday, I live in Canada so 19 is when I turn legal and can go to bars, drink, etc.

My girlfriend asked her to do the birthday on saturday instead and her mom refuses because "She wants to do it on sunday" 

Mind you, I live alone and my girlfriends been living with me for the past 2 months because my parents come and go from my mother country. My gfs mom doesnt know and she thinks my mom is here and thats why shes okay with it, shes super anal about her daughther, which is understandable. This morning she called her and started getting mad at my girlfriend for spending most of her time with me, and trully, one of the reasons she lives with me is that they recently moved very far from where my gf goes to school and i live significantly closer to my gfs school. Her mom refuses to pay for her gas and toll if she lives at her house.

Back to the original topic, shea decided to in my opinion do her birthday precisely on oct 2 cause its my birthday. She could have done it any other day thats not my birthday, its my 19th and it only happens once in a lifetime and its her moms 40s bday. Am I in the wrong here for being disappointed and sad?

Can you succinctly summarize the text in 1-3 sentences?
<bot>: gfs mom decided to do her bday earlier on my bday (On purpose i believe) despite knowing its my 19th and its the day i turn legal.