I am now 4 months post op and the amount I can eat varies day to day! Some meals I will eat for example a whole chicken breast, mash and veg, and then other times I wont be able to finish half of it. I find I am really inconsistent about my portion size and because of this I became worried and paranoid about it.
There really is no need to worry and if I was you, I would just trust the op and eat what feels right to you. If you read on here "you should be eating such an amount and then you find you cant eat that amount your going to think there is something wrong with you or if you find you can eat more, your going to panic the op hasnt worked as well for you as that person" I know i did!!!
Just eat the amount that feels right and stop when your full.
I still eat out alot because of work and having a high maintenance girlfriend, so I order something light all the time, e.g salads or fish alot of the time.
You will in time find what is the right amount for you and that will become the norm, i fully understand its hard up until this point, but try not to over analyse things, it will happen
xxxxx