Fasting for Someone Suffering from Bipolar Disorder and Depression

Hello, I am a 39-year-old man suffering from bipolar disorder and depression, which often leads to either a lack of appetite or an increased appetite, as well as sleep disturbances. For example, I can sometimes go to sleep at 5 in the morning because I couldn't fall asleep. My question is, given that I have previously experienced during a fast a critical situation where I can't sleep on one hand, and on the other hand, I become very severely thirsty. Am I obligated to fast? Initially, I will certainly try. The question is, what happens if I feel that it is already on the edge and it is very hard for me to bear. What should I do then? I would appreciate an answer.

Shalom and may you have a complete recovery.
You are not obligated to fast in this situation.
If you feel that you have the strength and want to start the fast, you can start. But as soon as there are adverse symptoms of weakness or increased thirst, you should drink as usual.

Shulchan Aruch, section Orach Chaim, chapter 554, paragraph 6.