Hi Kimyana
First, I just want to say that I completely sympathise with you. I'm 5 years out from my surgery and I've gained back about 8kg (or 17lbs). It's hard to shake and it feels awful.
I do think, however, that you need to be really really strict with yourself about how you're recording calories. Can you tell us here how you record them? Are you using an application like myfitnesspal? do you use the exact item/brand you ate to track? Are you breaking down each meal you cook into its parts and weighing them to track?
To be accurate with calories, you need to weigh and track every single item that passes your lips throughout the day. Including all drinks.
I say this because I'll be honest with you.. it's basically impossible for a person, at any weight, to be eating 600 calories a day consistently and not lose any weight. And that's when they're sedentary. 600 calories is a staggeringly small amount of food. To compare, 3 of the VLCD Optifast shakes made with water only are 500 calories a day.
Unfortunately, underestimating our calorie intake is very easy. I often will think oh, I can't have eaten more than 1400-1500 calories today. If I add it all up, on a day where I haven't been taking much care etc, I can easily have eaten 1800-2000 calories. It's not as much food as it sounds, and I cook all my own food and eat lots of veg. It's just easily done.
Without getting into it, I'm a doctor and I have seen people starve in the beds on calorie intakes more than 600. Even a person with underlying medical issues like PCOS or thyroid dysfunction should easily drop weight on 600 calories a day, especially when they're significantly overweight like you are (at 195lbs) or exercising.
I know it's not easy to hear and it's not easy to say, to be honest. But I think you need to be really honest with yourself about how you're tracking your calorie intake and aim to track by weighing every single thing you eat and tracking it accurately (ie if the item is not listed to track, then make your own item with accurate calorie content and then track it) so that you can get a true sense of what you are taking in.
