Most Helpful Guy
First off, it's pretty crappy to break up over text. Doesn't matter how bad of a relationship (unless it's abusive), you really need to do that in person. Just out of respect if nothing else.
To the point, get in touch with someone in his family or someone else who can find him. He needs help. If you can't get a hold of them, call the Suicide Prevention Lifeline and ask for help 1-800-273-TALK.