What would you do?

What would you do or not do if you found out one of your close friends was a “crazy” girlfriend. And by crazy I mean having 2 hour alarms to check his location. If he isn’t at home she asks why he is gone and where he is at. Wants to go follow him if she feels uncomfortable of where he is at (with the boys or shopping) anyways she said she isn’t 100% sure they are “official” but they’ve been dating for a month. I told her the alarms and checking his location is a bit extreme but she disagreed with me. I just found this out that she has been doing this since we started to hang out again last weekend. But I’m not sure what to do or what not to do