Should we be concerned about this?

I hang around with 5 other people, 4 of them and myself are male and there is one girl. We play sports together and we just hang around a lot. We all have been getting close and then the girl Nadine sat us down and told us shes gay. We don't mind at all. When we were at our friends house (Connor) Nadine and Connor were mucking about and Connor spilt his drink down her by accident, she was annoyed, so I lent her my hoodie. She changed infront of us all, it's like she has no problem with changing infront of 5 boys. I was just shocked, but I didn't say anything about it. It's just the way she did it without any morals. What i'm trying to ask is, should she be doing this even though she is lesbian. Im not judging nor trying to offend anybody but yeah she doesn't seem to care and it's not a one off either. What do you think??