New person - brother with aspergers, really need help

Hi, 

I'm really desperate for some need advice and help. 

A year ago my brother was diagnosed with aspergers. There's 4 of us siblings altogether but a big age gap between us (he's 18, I'm 29, sister 30, brother 27). 

We're very close and have a siblings watsapp chat. He feels most comfortable communicating by watsapp. He uses a watsapp titled with his name to message us lots of things e.g. when he's feeling rubbish or overwhelmed or panicky and anxious.

He lives with my parents. Over this summer when he was off from college, he felt he was a lone a lot and his mental health hugely deteriorated. As siblings, we arranged to see him at least once a week and also came home as much as we could and went on a weekend away, etc. But he had high expectations as an 18 yr old to be going out all the time, getting drunk. Thanks to social media he constantly talks about others doing things he isn't.

He masks his difficulties in social situations really well. We were told this in his diagnosis and I know he has friends at college - he did go out with them, and went for drinks and went to Pride in London, etc a handful of times. He just doesn't feel he makes close enough relationships. He also have very very high anxiety and a history of depression. 

After summer, he felt he couldn't go back to college because of the boring summer he had in comparison to others. He locked himself in his room refusing to come out or eat. My parents contacted the GP and they sent a crisis team out. Since then he has fluctuated. The college have said he missed out too much to go back this year and recommended deferring. My brother now sees his time in college and the friendships he has made as idyllic and recognises he is more socially isolated now.

He is refusing to see someone to talk to, refusing to hang out with us to do things, and very rarely engages when we offer help to do the things he says he wants to do (he says he just wants to work). Instead he sends us streams and streams of messages in the watsapp group most days about how he hates us (my parents included), how everything is our fault because we didn't make sure he had an amazing summer, how all his problems are because he has a rubbish family and nothing to do with aspergers. I've tried to get him to go to support about aspergers and he categorically refuses. He said he wanted to go to the gym so I signed him up and he hasn't been once. 

He spends all his time in his room, in his own head, and messaging us hateful messages. He will also message me normally but in a different format e.g. texts. These will usually be about what he should eat to go to the gym, though he hasn't gone. 

I'm just at a loss as to what to do. He refuses any sort of help, ignores anything we send him about aspergers (we send him stuff we think he can relate to like when that guy from Love Island said he had aspergers on instagram etc hoping it would help open a conversation with him). He just says he hates us and it's our fault his life is how it is. He doesn't leave the house or do anything. He says everything would be fine if he had friends and a normal life. We try to explain that perhaps understanding why he feels the way he does especially with making friends might help us figure out the best way to help him but he says he knows why he doesn't have a normal life and friends and it's because of his family.

I'm so so stuck. I am sure he is depressed as well as struggling to accept aspergers but he won't speak to anyone. His therapy is apparently hate messaging his siblings.