I don't understand why people are so hateful during such a dark time such as death. I'm so sorry for how your family is treating you, and I agree that the best thing to do is to stay away from them. Like the saying goes, "Misery loves company" and they seem to be making every effort to guilt you into something or simply make you feel bad. I think your silence will speak volumes that you will not be treated with such disrespect.
You lost your parents - what could be worse?

I think they treat you like crap because are hurting, but you are right in dealing with your grief in your own way. Being around destructive people doesn't help anyone, and one day you may have to confront them with this fact.
There is never a need to feel guilty about not seeing people who just make you feel bad. So yeah, stay way. Like I said, your silence will speak volumes.