Ok some background.
PIL are difficult - DH and I both agree wholeheartedly on this, there is no argument (fwiw, BIL and his partner also agree!). However, DH loves his folks and does want to maintain some kind of relationship. Long history of domineering/bullying behaviour, DH has had counselling to deal with it. They live at the opposite end of the country.
They have been retired since their 40s (inheritance), and they don't really remember what it's like to deal with the stresses of the working week. I think they don't really understand the difference between 'rest' and 'relaxation' - that, if you're absolutely exhausted by work, the things that you might normally find relaxing, like going to nice places, can become a chore.
DH has a VERY demanding job. Long hours, lots of responsibility, lots of aggro. And it's just got worse as he's been promoted. We tend to use the weekends for rest and recuperation. However, when we visit them, it is a cacophony of noise and activity for day after day - we are literally marched around visiting places from first thing thing in the morning to last thing at night. DH is harassed and stressed and upset by this (they are also terribly insensitive, which doesn't help). He frequently becomes ill during or after the visit, and we then hobble through the following week with him going to work and returning to collapse with exhaustion in the evenings, because he hasn't had the downtime he needs. It really bites into our quality of life.
For this reason, we are trying to have shorter visits with PIL. We used to do 4-5 days 4 times a year. We are trying to see them for 1-1.5 days more frequently, every couple of months.
So here's the issue.
We are due to visit their home in August, and DH outlined to them that we'd only be spending one night (2 days). (This has been clear from the start, but they have been conveniently ignoring it to now). All hell broke loose. FIL went into full emotional blackmail mode: 'This is TERRIBLE, your mother will be terribly disappointed, she's been so excited with all the days she's got planned, we're not getting any younger' etc etc etc. We hosted them for a long weekend last month, and we also saw them at a beer festival the month before!!
DH kept his cool but framed the decision that it was pressure from me. 'I need to spend some time with my wife, I've only been staring at screens the last few weekends, and she says she wants some time for just the two of us'. This is not actually true. We agreed together that we didn't want to do the long visits, and I have not, in fact, asked for more of his time! The issue is simply with the way that they are stressful to deal with and both of us reach our limit of tolerance (beyond which we are simply gritting our teeth) at about 24 hours in their company.
AIBU to think that this is likely to lead them to dislike and blame me for the changes? And that there might be better ways of handling it, like being more honest about the actual state of affairs? (I don't mind being told I AM being unreasonable if it is a good plan, I am just not sure we are handling this as well as we could).