When this woman feels like she made a mistake, she asks Reddit:
It's not a sharing problem as it is an organization problem. Hear me out. My boyfriend (26M) and I(26F) went to have some coffee/lunch last Sunday. He suggested having a coffee with his dad. I had some free time, so I said yes. Turns out that it wasn't just my boyfriend, his parents and I.
His bro (23M) and new girlfriend (28F) were there as well. No problem to me, it was the 1st time his bro introduced his girlfriend to us, and in general I get really nervous around people and going out in social events of all kinds. I'm socially awkward. My bf, he's a social butterfly.
Anyways, my understanding of the situation was the following: each person pays for their own. So, we sat down and proceed to order. My bf suggested we order the 'tea for 4' and his dad order something on the side. So I take my time ordering exactly what I wanted to eat. I'm vegetarian so I was careful about it.