59yo, No Children

That a girl!

I have not been there yet. I imagine it's beautiful and I've heard wonderful things about it -- it's definitely on my travel list! 

As for your diet, you seem to be on the right track already! My personal tips would be high protein (great for healing and starving off hunger). I aim for at least 10% of my breakfast to be protein and low slow burning carbs -- apples are one of my favorites as they are full of fiber and make you feel full. Throw in some healthy fats like Avocados and Coconut Oil...say in a smoothie. In fact, one of my favorite deserts is a pudding made of Avocados and Cacao.  I'm a health nut, so I know ever trick in the book to eat healthy without feeling like it is healthy as I love sweets and chocolate! 

Warning, this will be long! :) 

Bircher Muesli (created by a Swiss doctor/nutritionist who was very fond of apples) is an awesome start to the day -- and you can adjust it by adding more protein, (even a scoop of protein powder). Adding yogurt as you do is one way to do that, for a more powerful dose of protein as well as pro-biotics, I would use Greek yogurt -- it also has a high B-12 content, which is usually only found in meats. I see Greek yogurt as a superfood. I must mention, I mainly eat a strict plant-based diet, but I do believe that clean animal protein is essential and if I have no other option I turn to eggs, Greek yogurt and goat milk/cheese. Also, I'm not a nutritional expert -- this is only my opinion and what works for my family and I. I am pretty passionate about healthy living, so I spend a lot of my time learning about food and nutrition, and overall health and wellness. I kinda drive my kids crazy, but now they are getting older and starting to see the benefits of healthy eating and regular exercise. Back to the muesli -- do you soak your oats in fruit juice? If so, you can actually cut the sugar by soaking it in the Greek yogurt instead. I would add apples ( I like them sliced really thin...like a julienne style), dried fruit such as figs, dates, or cranberries pair well with apples. I would throw in a handful of nuts and seeds such as almonds, sunflower, and pumpkin seeds. This is another way to increase the protein content and healthy fats. Honey, I love it (even though it's a no-no for vegans) but it's also a superfood. I only use unpasteurized organic, local honey. 
Oh gosh -- this is getting long...see -- I could talk for hours about healthy food! 
Here is a basic list of complete proteins (again, I'm not an expert) -- meaning it has all 9 essential amino-acids that our bodies can't produce. We need 22 amino-acids for our bodies to function at it's best -- repair/rebuild, metabolism, digestion...,etc. 
Here's a list:
Eggs: I think they are the superfood of the human diet overall. Lot's of controversy about them, so do you research, ask your doctor -- but if I need a source of protein and don't have access to plant based -- I eat eggs. Also, I was recently prescribed eggs by my naturopathic doctor. I was struggling with belly fat, and he said I should incorporate a source of animal protein (long story) and eggs were his #1 recommendation along with 1000 mg of fish oil. 
Chicken Breast 
Hemp: Can be found in the form of raw shelled seeds, powder, flour. Hemp oil is amazing too. 
Quinoa: known as one of the richest sources of complete proteins we can eat -- also high in fiber, iron, B vitamins, and so on. If you don't currently eat Quinoa, I would recommend researching it and learning how you can incorporate it into your diet. Now, it can be expensive, but it's worth it, and a little goes a long way. You can cook or sprout it. I love to make a bowl of it and store it in the fridge to use for cereal in the morning. I love the multi-colored one, and top it with cranberries, slivered almonds, cinnamon (another superfood) apples -- basically anything I have on hand. 
Buckwheat -- kinda shocking, huh... I know. I love to soak buckwheat groats and use them as a raw cereal. I also make a raw bread out of them..it's more like a cracker. (Save that for another day) 
Now for the gross source -- I hate it, but it's very nutritious...Spirulina. You're on the ocean so you should have a healthy supply of that gross green stuff. I tend to lean to tablets, and or powder in a green smoothie -- but I hate the taste of it and find it very hard to mask. 

Dark Chocolate: Hahaha, I'm only kidding! But it is very healthy! 

Believe or not, greens and beans are rich in protein. Soybeans topping the list (again, controversial little bean) but they are touted as one the highest sources, and are on par with Quinoa (which is actually a seed but still plant based). I also love Edamame -- so good boiled in their shell topped off with some Pink Himalayan Sea Salt -- or just ordinary Sea Salt. ;) 

Chick Peas (my favorite, and I love hummus) and lentils-- especially in a hearty soup. 

And for greens, any dark leafy greens are going to be nutritionally beneficial, even contain protein, especially spinach and can be used in a variety of ways...smoothies (my favorite) and soups, salads -- I'm sure being a healthy eater as you are, you already know this. ;) 
Okay..I'll stop here, but you can see there are a ton of healthy protein options, all in which can be incorporated at some point in your daily diet -- even at 2 am. :0) 

Oh, as for your night time snack of almonds and milk, I think it's fine -- maybe a scoop of Peanut Butter or Cottage Cheese might be a nice change of flavor as well as more protein. 

Don't be too afraid of carbs, the body needs them for energy, among other things, just stick to slow burning carbs, and small portions -- besides you need carbs as part of a balanced diet.
As for the treats you mention, hey -- we're human and in moderation I say they are okay. I am a chocoholic, and I'm very serious when I say that -- put almost anything in dark chocolate and I will eat it! I relate to being high energy, I'm like an energizer bunny -- I actually think caffeine slows me down. :) Being high energy, it's even more important to balance with yourself with the opposite, calming activities -- which writing must be for you. Yoga is my zen time. Do you do yoga -- I realize you have limitations, but there are many poses you could work with. 
Good luck Julie!