@L0stinCyberspace
There's one thing that doesn't make sense OP. You say your DSS was fussy about food you previously made him and that's why you won't cook for him now.
Why then is he now eating the portions of food you prepared, with his DF?
She said earlier that the DP was adding things like garlic bread and pasta to DSS's portion. She's not there so who's to say he's finishing the lot? My DD would head straight for the garlic bread!
The DP on the other hand gets himself a nice large helping, and sorts out a dinner with the minimum amount of effort possible. OP, who has put in all the effort, gets fuck all, but for some on here that's ok, because how dare she consider her own health and plan accordingly when DDS is clearly starving. All her efforts should go on him, yes there's a fridge full of other food but we all know what how impossible it is to cook from scratch when you have a penis, so she must be in the wrong 
She also MUST be expected to provide entertainment for him, even if it means dropping her work. If she can't drop her work she can't take calls of a sensitive nature where he can hear so she'll have to stay at her place. But then she won't be spending any time with him, oh what a clearly evil stepmum, who will take care of him while she's selfishly earning a living? Not that lazy feck of a dad, surely?
Nope, it's all her responsibility now. She needs to stop thinking about her pregnancy and her career, and bugger the eating disorder too, the heartless witch.
By the way that was sarcasm, and it astounds me the way some women will rip another woman to pieces on here the second a stepchild is mentioned.
OP, he needs to replace those meals. I have a feeling you were making them because you know the lazy sod wouldn't cook the dinner post partum and you'd be expected to do it all while he sat on his arse. Have a serious think about spending your life with a man like that 