I've had the Party event occur and talked it out with the Best Friend to the point that I can occasionally hook up with them at night, but at some point they're is dating someone.
I've realized in another playthrough that the option to date them comes up if you chose to go forward with the act during the night you slept with them in spite of their roommate being in.
Does this mean that I can no longer date the Best Friend after that point? As in there's no chance of the Best Friend breaking up and giving you a second chance?
This aside, I do enjoy this game a lot and look forward to further developments!