Hi Sarah. I'm so sorry for what you're going through. I'm going through the same thing. I've struggled with acid reflux for the past few years. As well as depression, anxiety, and constipation. I occasionally experience stomach pain/burning.
The reflux definitely got worse when I was constipated. So the first thing I'd recommend is to eat more fruit, and perhaps lower your consumption of starch a bit. I have to have some starch, or I just don't feel satisfied. But if I eat too much, it seems to cause constipation. But you may be different. Just something to think about. Fruit certainly helps my regularity.
Water is also important for constipation. Like you, it sometimes causes me reflux. To minimize that, I try to only drink water 2 hours after a meal, and not within 15 minutes before the next meal. Again, that's my experience. Try it out.
Regarding the depression. You may want to talk to your doctor about that. I've certainly found that when I'm not focusing on my reflux as much, my mood definitely improves. Less depression and anxiety. So once you lock on to a good anti-reflux diet to reduce the symptoms, then try to find other (enjoyable) things to think about. Consider seeing a therapist or doctor for help in treating the depression. I took anti-depressants for many years, and they certainly helped. I'm off of them at the moment, but if I became depressed again I would go back on them in a heart beat. Also, I'm seeing a therapist now and that seems to help.
So, here's the diet that I've found helps me minimize my symptoms:
I eat 5 small meals a day, spaced evenly apart (around 3 hours apart).
Each meal constists of plenty of lean poultry (usually chicken breast) or fish (usually cod), some starch (I use white Jasmine rice, but try not to eat too much because I think it may contribute to constipation), a little bit of olive oil (about 1 tbsp, which is a lot to most people, but I need the calories), steamed broccoli and steamed carrots, a little iodized table salt (if I could avoid salt, I would, but I think avoiding it completely seems to bring on heart palpitations). And before each meal, I eat a very small apple (or one half of a medium-sized apple). The apples help me prevent constipation. Papayas are great for preventing constipation, too.
I don't eat gluten (wheat, rye, barley) or dairy. Also, I don't eat any spices, and try not to eat any foods with high acidity.
And I take 1 teaspoon of Carlson's Very Finest fish oil each morning. I don't know if it's helping with the reflux. It just has many other benefits (it helps prevent depression, and may also help prevent heart disease).
Other things to do: try not to not lie down or bend over after a meal; wait 3 hours after your last meal of the day before going to bed; raise the head of your bed (or mattress) to sleep at an angle -- or buy a special wedge pillow (I use the MedSlant wedge pillow, but it's a little pricey -- around $85); do not wear tight-fitting clothing or belts around the waist.
I hope this helps. Please also read the posts by Inez and others, as they contain a lot of good information, which has certainly helped me.