Help on family vacation

I (39F) am on a cross-Europe bike trip with my mom (63F) and brother (33M). My mom and I take these types of trips together and we tend to bicker a lot (we have different travel styles – I tend to like to journal, look for photo ops, read plaques etc, and she likes a more regimented get-up-and-go trip), so I thought that with my brother along this time we’d have a “buffer” and tie-breaker, and have a less strained time.

Instead, however, they are a team of two and are leaving me out. They are making all decisions. If my brother wants to do something (stop at a site, get a coffee/snack, take a detour etc), then she is okay with it, however long it takes. Ironically, she is suddenly okay with the leisurely travel approach that I typically prefer!!! They will take photos for/with each other, and if I want a photo taken I have to ask them to wait and take one for me too. Last night at dinner my brother said that I was unreasonable and everyone was scared to say anything or else I would have an outburst. (I am racking my brain for what he is referring to) and he scolded me for butting in to their conversation to ask if we were taking the ferry or dam route tomorrow. Last night they were making fun of me for laundering some bike clothes in the bathtub. Everything I do seems to annoy them, which makes me more flustered and I keep losing items and taking longer to do things (I have ADHD, among other diagnoses).

I am also on several meds that I take for various anxiety/mental health issues, which I am open about and am also monitored by a listened psychiatrist; my mom keeps commenting that she’s worried about all these drugs I’m taking, and “knows people” who have issues with these drugs etc.

We still have another week. My mom and I share a double room at each town and my brother has his own room. Everything is pre-paid and was very expensive. Yes, I have considered flying home. We all have the route so asking to bike separately may be an option if they let me. I tried to stay back from dinner two nights this week (just for a break) but they insisted I come (why?! When everything I do/say seems to annoy them!!?) and yes, I’m a grown adult and can stay back if I want to. But I’m just trying not to do anything else wrong.

TL/DR: I’m on a (non-refundable) Europe bike trip with my mom and brother and they are being mean, excluding me from planning, and otherwise making me miserable. We have a week left. What can I do to improve this situation ?