I am having a hard time figuring out if this is just behavior or the Alzheimer's I care for my father-in-law. Is it just me or the Alzheimer's?

ok I am having a hard time figuring out if this is just behavior or the alzheimer's I care for my FNL and he is ugly only to me, I feel like I am being petty over little things like doing dishes for example I cook,clean, do laundry for every in my home as I should there my family but then comes along the FNL and when I am done he will cut he finger nails in my living room or his room not over the trash. He puts his dishes in the sink and just leaves them or will just set his laundry basket in the laundry room and doesn't say anything to me, like he expects me to do it all. I have talked to my husband about everything that goes on, My husband does talk to his dad and he is good with him, but if I was to talk with him (which I try not to only as needed) he gets ugly. Then there's times where when my husband is home and I am washing the last dish he will ask can I help with any thing?? I think he does that just because my husband is there, I am getting more bitter as the days go on and my husband and I are at each others throats now and we hardly ever argue. I feel like I am coming apart at the seams.