2. She’s Making A Whole Lot Of New Friends…
It’s nice that your girlfriend is friendly and outgoing, but when she starts to hang out with a whole bunch of new people AND ditching the ones you are normally accustomed to, time to start worrying.
Here’s why, she might be looking for a new start, one where she can downplay your relationship or not even bring up the existence of her boyfriend, you. Another reason is that the new friends she’s made are part of the situation that allowed her to meet some other guy.