I suggest you plan every one of your meals and snacks like this: Each meal has 200 to 300 calories, each snack has 100 to 200, and you eat every 2 to 3 hours. Six meals, six snacks. This should put you between 1200 cals and 1500 cals. Eat all of everything you plan. Don't stop because you are "starting" to feel satisfied.
I'm thinking that you may not have a good sense of what satisfied feels like, and so you're stopping too soon. Could be you need some retraining.
I think I'd also consider seeing the doctor
just to rule out that you don't have some sort of condition that would be causing this.
Make sure you have a good balance of proteins, carbs, and fats.
1.7 pounds a day is too much. You are probably losing muscle and who knows what else.