Can someone tell me how this works?!

I have a 3month old and I breastfeed her. I don’t pump. AT ALL. She eats straight from the boob and also drinks formula when I’m not home which I’m home with her 95% of the time unlesss I run to the grocery store. Friday night I’m going out with some friends to a concert and I haven’t had an alcoholic drink in FOREVER and would like to drink. So, does anyone know how long I have to wait until the alcohol is out of my system? I can pump it out because I’ve never been able to get anything when I’ve pumped so I quit. So I’m curious how long the alcohol stays in the breast milk so I don’t pass any to her. Any advice please?!