Anthony wanted to be alone. He wanted to continue mourning Sorin on his own. No one else understood. They couldn't. No one appreciated Sorin like he had deserved to be. But Anthony didn't have the strength or the will to push Neville away from him. Instead, he let the Gryffindor pull him into his lap.
At Neville's words, Anthony found that he could cry again. And he did. Twisting around, Anthony turned into the bigger boy and let it all out. And as it usually went, once he started, he didn't know how to stop.