There's been an ongoing theme of Tony drinking through all of the films. In the first film, cocktails with the generals after the missile demo, and the benefit scene. In the second film there's his birthday party scene where he clearly gets out of control. And in Avengers he's drinking while talking with Loki. So the groundwork for Stark's alcoholism has at the very least been established.
The trailer seems as though someone wants to take EVERYTHING from Tony. Perhaps that loss will be the catalyst to develop a storyline which looks more closely at the alcoholism issue?
But in that respect, we may not have some of the other plot devices available that the comic writers had. Case in point: there was a point in the comics where Tony Stark gave up being Iron Man. He handed the mantle over to Jim Rhodes at that point while he dealt with his drinking problem. And at that point in time, nobody knew Iron Man's secret identity, so having Rhodey fill in as Iron Man worked. It wasn't until after Stark had come back as Iron Man that a new suit was developed specifically for Rhodes, and he became War Machine. But that storyline isn't possible since the films have done their own thing with regard to the timeline.