How to work through relationship conflict with the model?

How does the model work when you actually do want someone else to behave differently? For example.
I’m dating a girl who goes drinking with her girlfriends often at a bar.
I’d like her to drink less with her girlfriends and only do it without single men around.

I know it’s outside of my control but I do have a standard I’d like to withhold. I’m not comfortable dating someone with those behaviors since I’m focused on health and fitness. Do I speak honestly and openly about it to them? Because, I wouldn’t want to continue dating someone that has these habits. If she’s willing to change them then I’m willing to stay in the relationship. Do I just change my thoughts? What is suggested with these circumstances?