Hi iknow, welcome to PC. I'm so sorry you feel like everyone hates you (from your nickname). I can assure you that you'll find some really good support here. I like you already!
I haven't lost a parent, but I have lost a loved one. It can be pretty devastating and it's not something one can just get over. I know for me, I really backed off from people because I was just so overwhelmed with things. It didn't mean I didn't know the people cared for me and it didn't mean I didn't care for them, but I just couldn't add anything else to my emotional plate. And if someone added something emotional to me (such as getting upset with me or anything, even very trivial things), I was more apt to back away further.
Maybe the best thing is to just be there, not in words so much as actions. I had a very good friend who would call and just leave an encouraging voicemail sometimes. Never asking me to call back, just wanting me to know I was cared for. I would get little encouragement cards in the mail, just to let me know the same. Maybe you can do something along those lines? Maybe he just needs to know you are there, even if he can't mentally and emotionally reach out right now. Maybe you could cook him a meal and leave it for him (without staying). Send some cards to him (even though you live in the same area, it's nice to get mail) just to encourage him. Just be there for when he comes back mentally.
Good luck with this and please keep us posted. It's hard to know how to handle situations like this. We want to support you.