I visit my parents about one time per month, for one to two days. Sometimes I manage to visit them twice, in rare cases I have to skip a month. So we see each other in person regularly (and, for sure, during some holidays, but this is about the shorter visits.). They know that I can't visit them more often. They live about 3 hours away, and I've been out of the house for around 4 years now.
While my dad is pretty relaxed about it, my mom then tries to have everything in perfect condition and planned exactly to my tastes (e. g. musing about the whole week and asking me what I would like to have for dinner or taking care to get me a little present). She also ensures to take care of me in other ways, e. g. by buying me useful items I may need.
She is not a helicopter mom and never was. So don't get a wrong picture of her. She is also not interfering with my day-to-day life (from afar) - it really just concerns her preparations for my visits.
I appreciate her efforts very much, but I'm sometimes a bit indecisive and also don't want them to plan everything according to my wishes. It causes her more stress than I would like. Sometimes she even mentions that in passing - something like
Mom: I couldn't get X done because I had to do Y for you and then ...
Me: I told you that you needn't have done Y for me.
Mom: It's fine! I'm always glad when you visit us!
Mom: This week was very stressful for me. There was ... during the week, then your visit over the weekend. And now I still have to do ...
Me: I'm sorry that I caused you more stress. Why didn't say anything?
Mom: Oh no, it's nothing!
But I know that she causes her too much stress even if she doesn't say anything.
What I tried
Usually, I try to tell her that she doesn't need to make such a fuss about it, when she asks me ("It's not necessary that you ...", "I don't know, just like how you would do if I didn't come ..."). I fear that I come across as nagging - especially if I approach it from the angle of how I feel about it - and she answers that I needn't worry and that she is always happy when I visit. My dad is of no help in this issue.
My goal is for her to treat my visits as if I was still living there - like nothing overly special. After all, I visit my parents to see them, to spend time with them and to talk to them. And I would like her to be able to enjoy it without unnecessary stress.
How do I go about telling my mom, that I appreciate all she is doing for me during my visits, but that she needn't cause herself too much work and stress?
Once I even got the idea to surprise them (I had made sure beforehand, that it wouldn't interfere with their plans), but it caused her even more trouble.