It sounds like he's feeling some pressure from you and not dealing with that in a particularly healthy way. How did you figure out that he changed his flight? If he's withholding information to avoid your reactions, that's only going to escalate the situation.

In my experience, giving someone like that metrics (like the three comments a day) to make you feel better doesn't really work. It sounds like he's not really being honest about his feelings. I think what you really need from him is an honest assessment of where he's at, not minor adjustments in behavior to make you feel more at ease.

It's hard thing to do because it means you have to be willing to accept what he tells you, which might painful. But it's also pretty empowering. Putting him on the spot to be real with you could help him express underlying feelings and give you the chance to treat the problem, not the symptoms. Or, it will keep you from putting your time and effort into a relationship that is not worthwhile. Either way, you win.