As if you don't know, that there is Jesse Pinkham from Breaking Bad having one very fucked up day (in the episode "Granite State"). He's just witnessed his ex-girlfriend, Andrea, get knocked off by Todd, whom Jesse has appositely summed up as "that dead-eyed Opie piece of shit." Todd belongs to criminal clan of ratio-instrumentalist racist rednecks and he's the least emotional of the bunch when it comes to taking care of business. He shot a child witness last season without flinching, now terrorizes Skyler by threatening to kill her baby girl Holly should anything come out to the cops about Lydia (Todd's crush and criminal business partner), followed by murdering Andrea to prove a point. The point being that Jesse better keep cooking meth for Lydia and the rednecks or he'll kill Andrea's boy, Brock, just as easily as he did his mother. Contrary to the cannibalistic hillbilly savages that Hollywood tends to depict the under-employed and -privileged white Southerner as, Uncle Jack's family are real cold motherfuckers. Everything is about profit and risk assessment. They are the smartest criminals in the the entire five season run of the show. And they're probably the most evil, too, for that same reason.
Andrea's murder is the most heinous of all in a story that has featured many, many murders. Why? Because of its iniquity: she was killed because of what it would mean to Jesse, not because -- as was the case in killing Hank or even the boy witness last season -- she had anything on Todd's family or business associates. In terms of the criminal ratiocination that makes up the show's diegesis, her death was the most unfair. Hank was actively going against the criminals, so chose to put his life at risk. And the boy on a bike, at least potentially, had knowledge that might've been actively used against Walt, Todd and the others. Andrea had nothing on which to ever actively go against the rednecks. Instead, she was killed as pure means to an end of which she had absolutely no knowledge or ability (potential or actual) to alter as a free agent -- that end being the continuance of Uncle Jack's family business. Her death was pure collateral damage, in other words. Hank went out with honor, accepting his fate as a result of trying to live as a moral agent, Andrea's life was simply used by others.