Caregiver advice

Cold Moon
Anyone have experience with their SO being the primary caregiver to a dying parent? My bf is 30 and has been living with his parents the past 5 years after his mom was diagnosed with cancer for the second time. She has stage 4 lung cancer, it has spread to her liver and lymph nodes. She's also had two major heart attacks and smokes about a pack and a half of cigarettes a day. I like his family but I've noticed over the past two years that my bf literally gets NO support from his dad. His dad works part time, doing food shows, so he's gone for weeks at a time. His parents constantly fight because they are both very manipulative and hurting. His mom always talks shit and tries to get her son in the middle of their fights. He's even nervous about leaving even for a short weekend out. I look at him sometimes and he'll be staring into the distance with the most lost expression I've ever seen. Total heartbreak is written all over his face. I'm at a loss as to how to help him. He's told me before he doesn't talk about his emotions, he just bottles it up. I don't press because I know that he doesn't want to talk about something he lives 24/7.. How can I make his life easier? I cook and do housework if needed, hang out with his mom. I try to do what I think is needed and try my hardest to be a support system for him but idk if its enough. I want to stop his hurting but I know I can't. I need advice. Has anogone else gone through something like this?! I'm in over my head and I just want my bf to be happy and not stressed.