If you're having a bad day the main thing on the mental side is realizing that I'm having a bad day and thinking about why and then just kind of re-prioritizing and saying, "I'm going to let myself have this bad day, but tomorrow I'm going to get back on track. " That's pretty much it. We all have them. You do have to let yourself have them and then go within and figure out why you're having it and prevent it from happening again.
The Marine Corps is proud of the fact that it is a force of combined arms, and it jealously guards the integrity of its air-ground team.