Hermione cared for him until she couldn't any longer, putting off a trip to the hospital, at Harry's persistent request, until he finally gave in to Hermione's pleading. They both knew they didn't have the money to put him through treatment if results were less than ideal, and they both knew that coughing up blood in a sink did not equate to perfect health.
They had had scares in the past. They both worked dangerous jobs. Hermione's infected ankle cut from a dropped knife at her waitressing job eventually healed but left a nasty scar. Harry's broken pinky from his construction job was still crooked, but at least it had stopped hurting. Hermione caught a particularly bad case of the flu one winter, but, especially after Harry had lost a telemarketing job, they were in no place to spend on hospital bills. They always overcame without a trip to the ER; they always found a way to grit their teeth and carry on, but Harry didn't look so lucky this time.
Lab work came back with news of a malignant tumor in his left lung, and it became clear that Hermione had no choice but to force Harry to receive treatment. He knew it was expensive and insane to allow their funds from years of hard work to be drained on him, insisting that Hermione bring him home and just hope for the best. Hermione was fierce, though, and refused to accept Harry's answer. He would receive treatment, she would make ends meet, no doubts or hesitations.
Of course, she had no plan. She had no way of knowing how she could possibly find a solution. Her 3 jobs were nowhere close to sufficient. She considered prostitution, but...no. She looked into the drug trade but figured that, with all of her criminal warnings in the past, being caught dealing would be less than forgiving. She fought for her situation to work. She paid for nearly half of Harry's chemo treatments by working more hours than she had in a day, struggling to stay awake and healthy herself. But when she collapsed from exhaustion at work during a graveyard shift and was early dismissed around midnight, she realized she had pushed the envelope, stretching herself as far as she could to try to make things work. Harry's next payment would be required soon, and she knew that without it, the hospital would stop delivering treatment. Harry had just begun to show signs of improvement - for him to stop now would not only set him back further, but it could even kill him faster. He needed his treatment, and Hermione needed to help him. He was already doing more than he should have been. He was working from his hospital bed, completing online jobs in the hopes of supporting her somewhat through the financial struggle. He was guilt-ridden, but there was only so much he could do between the fits of nausea and exhausting, painful treatments.
It was on her midnight walk home that she saw it. A man, hooded and clad in all black, approached a park bench, quickly duct taping a package to the bottom of it before running off into the night. Hermione saw no one in a wide radius of her, and her curiosity got the best of her. She crept up to the bench, feeling underneath until her hand rested on the package. Its contents were heavy, wrapped in a black trash bag, but she could feel a general outline of the interior, a cold metal. She gasped, immediately recognizing the shape, and panicked. She stuffed it into her sweatshirt pocket and ran out of the park, not stopping until she reached her front door. Her eyes were wide in disbelief, and she nearly passed out again with the realization of what she had just done. Before she could let her imagination get the best of her, she made her way inside, opened the package, and read the contents of a note inside.
In the bag, she found instructions. An identity, a location and time, a phone number, and a wad of cash. They identity read: Johnathan Alden, 34, abusive husband, works at Merildo Co. The wad of cash was more than Hermione had seen at once. A note tucked into the stack read "Second half to be delivered upon completion of job. Call number when finished"
Finally, she reached in the bag and pulled out the final weapon. A gun. She didn't know what kind of gun it was or how it worked, but she knew it was powerful, and she knew it was deadly. And if this was what she would have to do to keep Harry alive, then she would do it. A taken life for a saved life, and she was ready.