Law, where did Sasuke needed to hide in between corpses so he wouldn't get killed, he saw everyone that he liked including his littles sister die because the corruption of the WG that just wanted the mone that was coming from, then he joined the pirates where he was kinda treated like shit, and again he got called monster and was ostracized by everyone in the hospital where Corazon took him adding to the pain a little more, and we know he'll lose Rocinante, the only friend he made in the Doflamingo family, and the fact that he had to live a couple of years knowing his death was imminent.
Sasuke had a hard past yes, but he was always loved as a kid and he could've got any friends he wanted, but since he's a douche, well he barely made friends.