<human>: Can you summarize the given text in a few sentences?

Firstly I am on mobile so I apologize for any formatting errors. 

I was in a few classes with a guy I'll call John. He's a nice enough guy and after graduation he moved across the country for grad school. While on the opposite coast he met "Sarah". From what I can tell based on Facebook they dated for about a year, however she recently broke up with him and (apparently) blocked him on social media. 

Now John has been very depressed about this. He has posted daily updates about how his life sucks and she was the love of his life and yaya yada. However they've become increasingly desperate about how much he misses her and tries to tag her in posts but cannot (how I know she has blocked him). I know her name based on one of there posts and it wasn't difficult to find her. My question is: should I let her know about this? I don't know if she's completely trying to cut him out and doesn't care or if she should be careful. John isn't a violent person but I have no idea if he'd actually do anything. If it's worth anything, he is currently back home while Sarah is on the opposite coast.
<bot>: Aquaintence got broken up with. Is very depressed and writing pleas for his ex to be with him. Should I tell ex about it?