If you are currently helping someone go through this disease - or suffering from it - all I can say is: hang on there.

Dealing with irrationality is one of the most frustating feelings out there. You will get very tired sometimes. You will get overwhelmed. Nevermind. They are having the worst of it.

Keep going. You owe it to them to comfort them, no matter how many times. Remember two things: It's not their fault, and it will get better.