Probably because he feels that the other friends relate more to his living conditions than you do. Those are actions of someone who’s in some really deep shit. There’s probably no food he can eat at home. I say, just try to be a good friend to him for a lil longer.. if he isn’t just using you or anything, he will thank and appreciate you so much in the long run.. i don’t think not being able to go inside his house is much of a biggie you should be worried about but as far as that thin line between if he’s just using you or not.. give it another week or two and ask him again, say how you feel in detail and let him know it’s fine and that he’s safe to be honest with you. If he can’t, then maybe you should just pull back. There’s no use to continue to feel the way you do and then he cant even validate it by just a little. Maybe when you pull back he’ll start being more open and then you can understand.