Dont want my friendship to end, please try and answer, i know its long, but i need to work this out. thanks?

well, me and my friend have met up after school every friday for like 7 weeks now. and i want to explain this properly and correctly. This all began when i met him. he's really sweet, and he has a bad home life. i've experienced this first hand. his little sister is quite frankly a b%$@h. she is really rude to him, and never speaks to him. She never gets in trouble for it, she just gets away with it, it makes me soo angry. she just demands everything and gets all angry when he doesnt do as she asks. he also has an older sister. between his 2 sisters, they have over �30,000 worth of stuff. cars, laptops, horses, stables, the lot. he, has an xbox, an ipod and a cd player. thats pretty much it! :( his sister recently got a iphone 3gs, and was in a massive mood on her birthday, becuase she couldnt text people yet. she is soo ungrateful, and gets away with it. his mum, is very nice, she has her shouty moment, but otherwise very nice :) his dad. i dont know what to think of him. he is very strange. the first time i went to his house, he said 2 words to me. "hi" and "bye" yesterday when i went round, (this was the 2nd time) he said nothing to me, never even looked at me. my friend is stuck at home, with his xbox, and thats it. he doesnt have that many friend, his sisters, well u get the idea :( and his dad doesnt speak. I am the only person he truly trusts. I'm the only one he speaks to about family, and as he said to me, "your not a friend to me, your more of a brother to me" and its true. when he's happy, im happy. i am amazed at how bouncy and happy he is at my house, or when im round at his, its like a new person has taken him over. he is very close to me, and is very happy to be with me whenever. He actually told me he wanted to live with me instead. :) but at the same time, thats not a good thing. i klnow that, it would never happen. its not right, and his parents wouldnt allow in the first place. But its what he truely feels. i feel empty when he's not around. he makes me feel worth something. im a large part of his happiness. when he is sad, i try my hardest to chear him up. And now the bad news. i have not hd after school band for a month. it starts up in August, and we can no longer have our friday meet ups. until january. when i remembered about it, it hit me like a tonne of bricks. i feel pretty terrible about it, cause if im honest, hes the most important person to me, and to see all that has happened go to waste very soon. will pull us apart. we need each other, and even when he leaves my house on a friday, its hard for him to leave with becoming sad. i cant let this happen. im busy mondays wednesdays and fridays. and i fear my mum will say that i have to have days off. Even his mum thinks im a brother to him really. she mentioned i to me. i cant let this slip away, and really need some guidance, im going to see my pupil support teacher about it. i cant let it end. because even when it hasn't happened, im feeling pretty terrible. i cant let him down, i cant stop our meet ups, he's lost without me. im not saying that because im full of myself, i need him too. its just like.............. mind bending really. thanks to everyone who helps out. :) i really appreciate it :)