When someone was involved in the use of heroin circa 1968 they would heat the drug in a spoon. The term Matchstick Men comes from this time as they used paper matches and split them from the bottom up to make them stand like a small tripod. Then the tip of the match was lit and the spoon held over the flame thus cooking the heroin. This is where the term Matchstick men came from. The reference to a "funny kind of yellow" in a the eyes may have been the breakdown of the liver from abuse of drugs and alcohol which are synonymous with causing liver failure. The references to not being left alone and Matchstick men and you may have been the addiction as it is always haunting and never leaving them alone. The original groups did have members that were into drugs although it is not mentioned which members or what type of drug they were using at the time.