Really feel for you, Bupcakes. We had this for years, although it was my mum's deadbeat brother. We always had gran (mum's mum) to our house, and so we had to invite arsewipe too. He lived with gran all his adult life, being waited on, but when she got ill he couldn't possibly look after her (despite not working) and she had to go into a nursing home (which plagued my mum with guilt, even though she was very ill and disabled herself, and still worked f/t and had 3 other siblings 
)
The Christmas invite pantomime went like this: Mum would insist deadbeat uncle came to us, dad and I would roll our eyes. She would send deadbeat uncle (DU) a Christmas card with £100 in it because she felt sorry for him, and there would be a nice letter to ask him for Christmas. No response. Mum would phone him a few times before he would eventually answer, the week before Christmas, and announce that he would come, BUT we should remember he didn't eat turkey. Or vegetables. And that we would need to come and collect him, at a time prescribed by him. And then we would need to make sure dinner was over to run him home again at another time prescribed by him so he could go out with his friends. My mum would agree to all this.
Except that, from the time I was 18 or so, it was me who cooked the dinner (mum not well enough, and I wanted to help her out), and me who had to go and pick the tosser up (dad getting gran from nursing home) and me who had to run him home again. I remember digging my heels in over the "he won't eat turkey" scenario. Fucked if I was preparing a separate dish for him.
After being picked up, he would swan in, empty-handed, and announce he hadn't brought any presents, but wouldn't be shy about accepting whatever mum had forced us to buy for him. I always wished he would even bring a token bottle of crap wine, or flowers for my mum to say thank you, but needless to say he never did. He wouldn't even have anything for his own mum, who was so pleased to see him there 
He would proceed to moan about every aspect of the meal (well, in his case, just potatoes 
) then remind me countless times that I had to drive him home in however-many hours/ minutes. When my other aunts etc turned up to see gran, they had to sit in a separate room, as another of my aunts hadn't spoken to him since he smacked her in the face a few years previously because she suggested he could get a bus somewhere. A lovely chap.
Fast forward a few years- after my gran died, we STILL had to have DU for Christmas dinner. He refused to come to my wedding, and sent a crappy bit of paper saying he would buy us a gift, as that must be what we wanted. I didn't reply.When my mum died, he didn't reply to any of my dad's phone messages, then turned up on the morning of the funeral and upset everyone, insisting he help carry the coffin etc.
I have never seen him since, and assume he is the same sad bitter old turd in his near 60s as he was in his 30s. Sounds a bit like your brother, bupcakes. My gran spoiled him and did everything for him, catered to all his faddy eating, put his bets on for him, gave him money, everything. I loved my gran to bits, but I really do think a lot of the way he turned out was her fault. It has had a real influence on the way I treat ds (only boy, youngest)