You can eat meat. Ham slices wrapped round a stick of celery. Chicken parts providing they really are chicken. You can tell because the bits are called leg, breast, wing, fillet etc. Avoid it if it called dipper, nugget etc. Mattesons smoked pork sausage is good and indeed sausages if they are not the cheap totally fat kind. I like Cumberland ones. An omelette also goes well occasionally.
Your dietician may mislead you. Mine gave me the NHS party line and wrote me an action plan which included, "Carbohydrates at every meal". My nurse blew a gasket at this but kept her counsel since she has to toe the party line also.
Cut out sugary drinks and don't have sugar in that tea. Cut down on flour products, rice, potato.
Above all, don't go hungry ......have another smoked sausage. Well, you know what I mean.