Pushed away as a caretaker/girlfriend

my boyfriend and i have been dating just over a year; we met while he was in remission from cancer, but about 6 months in, he unfortunately relapsed. it was such a scary time for us, but somehow our relationship stayed strong and good through numerous doctors appts, treatments, months of him living in the hospital, etc. His treatments have lessened significantly in the past couple of months, but it has brought change to our relationship. I got into trouble at my work for skipping so many shifts to be at every single appointment, so its been harder for me to be there physically for him at those appointments. And since this, he’s begun to shut off from me emotionally, and has entirely shut off from me physically. Sometimes i literally wont know whats going on with him until i hear it from a doctor or one of his family members hours or even days later. Most recently, hes stopped communicating with me altogether. I work long hours to make ends meet, and when i come home i pretty much get ignored from the moment i walk in the door. Without the emotional and physical aspects there, I definitely feel lonely now more than ever. I tried talking to him about it, and he pretty much told me that his recovery will always come before me, and that he knows he’s put me on the back-burner, but it’ll stay that way as long as it has to. Now, I have always told him that his recovery should come first, and that i will always support him in any way i can, but i just dont get why hes pushing me away now, when we have been through worse situations together? The diagnosis/prognosis is slowly becoming less bleak, but its like the better the outcome, the worse our own outcome is. I guess I’m just wondering if anyone else has felt like this, because its really taking a toll on me. I love him so much, and I would stand by him no matter what - i’m just starting to feel like hes the one that wont be around to stand by me.