Hi Sara,
When I was diagnosed two and a half years ago my husband was my lifeline. He was there for me throughout surgery, radiation, etc. I am a "silent sufferer" so find it hard to let others see me in pain, I want everyone to think all is well. So my husband had it pretty easy as far as the caretaker role was concerned. I remember when I hit a depression after treatment ended and I would have times of feeling unreasonably angry with my husband. He considered it all to be over, cancer was in the past, no more talk of it, move on. He didn't realize that I was just beginning to deal with the emotional side of it all now that physically I was beginning to improve. Of course, I didn't open my mouth and tell him this either! I went along with it and kept my feelings to myself, which created a slow burn of anger at him, as I watched him live his normal life and I still had a sore mouth, ate liquid food through a tube and felt terrified of dying every minute of the day. I kept my kids at arms length for a time thinking it would help them if they ended up losing me to cancer. The mind is a true enemy when battling cancer.
Maybe your husband is feeling some of these feelings? It sounds like your marriage was strong before all of this. I agree with Mark that he needs a reality check but I also think you should ask him if he feels resentful about something else and manifests his feelings with the silly talk of how you don't give 150% (who does?).
I talk about my cancer now with my husband. I finally just told him one day that I might die from this and it was something I needed to talk about, even if that meant keeping cancer as part of our lives, meaning his and mine, not just mine. Our marriage now is stronger then it has ever been, with a deeper level of respect and understanding.
I hope you work through this.
Minnie