Struggling with Increasing Chronic Illness Symptoms and Mobility Challenges

I'm awaiting an appointment with neurology which could take months or even over a year, in the meantime the list of chronic illness symptoms is increasing - although the severity of some symptoms seems to fluctuate - and about half way around a museum exhibit I needed to use one of the portable chairs they provide due to pain in my feet and legs. I felt emotional about it afterwards, as I accepted I couldn't make it around the exhibit and very much wanted to, but it was the first time I've had to use a support like that and it feels like a turning point with regards to my health. I've got mixed feelings about it, but a friend pointed out that I would be (and have been!) so happy for another friend if they were able to use an accommodation which made something easier/possible, so I'm trying really hard to feel positive about that aspect, while also allowing myself to feel sad about my mobility and various other things becoming more challenging.