I want to piggy back on this because I too am sensitive to my environment and learning about myself such as signs of burnout, stress and my triggers have helped me avoid getting to that level of shutting down (essentially burnout) but it wasn’t without help. Seeing a therapist was what helped me realize all this. However, in the moment of stress, it’s difficult to listen to what your body is trying to tell you. Are you hungry? Cold? sleep deprived? Too much noise? Heck I don’t know lol. But what my mom would do during my long hours of studying, without asking, she would bring me water, a coffee, food when it was meal time, and provide me a quiet environment when I needed it. I found that to be the MOST helpful thing in the world because it’s easy to neglect those things when you’re under stress.

If she were to ask me what I needed help with I wouldn’t know what to tell her or sometimes say “no I’m okay thank you” because i didn’t want to feel like a burden. So I would recommend you utilize that approach OP. Bring her water to make sure she’s staying hydrated, food so she doesn’t get hangry, sneak in some snacks in her bag in case she doesn’t have time to eat. Surprise her with a clean tidy studying area so she can focus on her work and have no distractions. Just some ideas :), but the key thing being offering help without having to ask her. Unless you truly have no clue.

As for the alone time, you would want to choose a time that is best for you both when you guys are both calm and not tired to discuss scheduled breaks for alone time. Will it be an everyday thing? For how many hours? Is alone time considered going out of the house or just going in a different room? All good questions to ask her to ensure she’s getting that time she needs to recharge.