I can't imagine. I think he would just be destroyed. I think he would have leaned heavily on Bones, but it would never have replaced the empty thing inside him. To have been that close with another person -- and I don't even mean this from a K/S standpoint necessarily, it works for K&S too -- and to lose that person, to know he died for Jim (and the others, but for him)...I don't think he could ever recover from that. It would haunt him for the rest of his life. I imagine he'd see Spock's hand against every pane of glass he walked by.