I found this definition which I feel
is fairly accurate may or may not be accurate: The Pink Cloud Defined
Early recovery is often referred to as a rollercoaster ride because it involves a mixture of great highs and great lows. Emotions that have been anesthetized with alcohol and drugs suddenly awaken, and feelings can be particularly intense. As the body and mind adjusts to this new life, there can be rapid changes in mood. There will usually come a time though, when the individual hits a smooth patch. Life will feel wonderful and the future exceptionally bright. Staying free of addiction now feels effortless and the individual may wonder what all the fuss was about.
The term pink cloud tends to be used negatively to describe people who are too high on life. They are individuals who have lost touch with reality and are now living in a fantasy land. The emotions that this person is experiencing do not properly reflect their actual situation. The pink cloud syndrome in addiction recovery was first described by Alcoholics Anonymous.
The above information came from http://alcoholrehab.com/alcohol-rehab/pink-cloud/
Anyone else want to chime in on examples or explanations…please do!