How can I cheer up my boyfriend who feels like a failure at life?

We've been together a year & I've known him for 2. The year before we got together he picked up drinking and smoking after his grandmum passed away. The semester after we got together he got kicked out of his university for not attending (therefore failing) over the year he was still enrolled. Keep in mind he had a 3.8 before his grandmum passed. His family lives four hours away in Savannah while we live right outside of Atlanta. He gets really depressed a lot & doesn't know what he wants to do with his career now. He talks about the military, being a k9 cop, a firefighter, something to do with gaming, and a journalist. He's a great writer, knows a lot about the music, film, and gaming, and was a military brat like I was. He's 22 & I'm the main positive thing in his life. How can I help him feel better about himself or to be motivated to better himself?