Sorry you're having a hard time!
I fast 24 hours on most days, and have done countless fasts up to five days in duration. Not once has my appetite diminished with multiple days of fasting, and if ever I thought about food for longer than two seconds, I would cave and eat; but this is me, and many others claim to lose appetite once they enter ketosis, which typically occurs between two to four days of fasting.
An option to make fasting theoretically easier is to enter ketosis first through a ketogenic diet, but this approach does not diminish my personal appetite while fasting, as I've tried this several times. But, everyone is different with diet, appetite, and mental strength.
Personally, I find fasting longer than two days to be a big mental challenge, and time tends to drag. Many times I've set out to fast up to five days, which is potentially the optimal duration based on some authophagy theories, but I would oftentimes break mentally between three to four days, as I would question the lack of proven scientific evidence with fasting for health reasons, etc. I've only made it to five days a few times.
FYI, anyone who goes longer than five days and wishes to break their fast then there is something called refeed syndrome to be mindful about, because there is a proper way to break an extended fast lasting longer than five days. People can end up in the hospital if a prolonged fast isn't broken properly, and in some cases refeed syndrome is deadly, which might not be the desired outcome if one ultimately decides to end the fast. Refeed syndrome is illustrated with some of the American prisoners of war rescued from Japan after WWII and with rescued holocaust survivors. Others inexperienced with fasting have experienced refeed syndrome, and one can read their stories on line.
There is at least one anectodal story of someone who intended to CTB through fasting and this person obtained clarity of thought after a week or two of fasting. This particular individual went on to recover, and he became a life long advocate of extended fasting to treat depression. This was in the eithteen (?) hundreds.
As another aside, the Russians have/had a track record of treating mental illnesses through fasting for between 21 and 30 days. A Russian physician claimed to treat and cure many forms of mental illness including schizophrenia with these fasts, and he conducted these inside Russian assylums in the early 1900s.
The moral is anyone who engages in a prolonged fast, be prepared to potentially have your mental state altered favorably and be knowledgeable as to how to successfully break the fast should you choose to do so.
