I work from home 2 days per week and am in the office the other 3 days. DP doesn't work, their choice. They have income from other sources.
The nature of my work requires me to be at my desk continually when working from home, unless I have arranged cover (ie during my breaks). Think along the lines of receiving emergency services calls. It's the sort of job where I have to be working during my shift; I can't stop working for a while during the day and it doesn't matter because my manager will be happy as long as the work "gets done" later that evening for example. By the evening that work will be gone. It's a demand-led job that's very much in the moment.
I get 2x 15 min breaks, 1 in the morning and 1 in the afternoon, and a 30 min lunch break. Often by the time I have been to the toilet, made my lunch, replied to any personal emails or messages, taken the dog out if necessary, my breaktime is over and I need to go back to work.
Yesterday DP was out all day and came home just as I was finishing my afternoon break and heading back to my desk. They asked if I had sorted the laundry, I said no I haven't had a chance. This led to a huge argument about how I had been at home all day why haven't I done the laundry. I said I'd been at work but could sort it once I finished at 5pm.
DP's response was that they had also "been at work" (because we have a significant life change coming up soon so they had been out doing some of the admin we need to prepare for it). The argument finished with DP saying, "I would like you to sort out the laundry when you're at home". They said that I expect them to do everything. I said I don't, I just can't always do laundry during my working day but am of course happy to do it after I finish work for the day.
Who is being unreasonable?