VERY! Any withdrawal is very difficult! You should be in a rehab facility at least! As they are professionals trained to guide patients through the arduous process.
Can be very. Cocaine does not have a real "withdrawal, " since true withdrawal can be treated by giving the person the drug they are using. What people are experiencing is the absence of Dopamine in the brain, resulting in depression, sleepiness (often sleeping for a day or more), sometimes psychotic thoughts and paranoia. This is followed by increasing Cocaine craving and relapse. Some medicines may help.