Okay, see, this makes sense. 1900 is your maintenance calorie level.
However, to lose weight, you have to create a calorie deficit. In essence, temporarily "starving" the body of what it needs to maintain.
The industry standard on this is 3500 cals = 1 lb. So, if you create a 3500 calorie deficit a week, you will lose 1 lb a week. 3500/7 = 500, so if you ate 1400 calories a day, you would lose 1 lb a week. Cut more, and you lose more rapidly. You would have to go below half of your basal metabolism, so 950 as evidenced by the 1900 calories, to even touch your metabolic rate.
The "starvation mode" myth is really that after you hit half your basal metabolic needs, that your metabolism slows down a bit, but not enough to really affect weight loss in that moment ("bounce back" and other stuff notwithstanding). To hit this, you have to go low enough that your calorie deficit is so high that you will still lose. This is why you don't see a fat anorexic.
As to the exercse = calories burned = therefore I can eat more thing, I tend to err on the side of ignoring that. I don't tend to believe that I am burning as many calories as "they" say I am (i.e. it is not an exact science)...
Lyz, yes. Maintaining is definitely not the same lifestyle as losing. Same idea, but with more "give".