With regards to cheese's addictive nature, there have been experiments using the drug Naloxone, the same thing they give to people who have had a heroin overdose, it basically stops the effects of opiates on the brain, what they found with foods like chocolate and cheese was that the interest in the food greatly diminished after the Naloxone had been administered, showing evidence for the casomorphin's having a similar effect on our brain as regular morphine, although the dose was very small.
As for the substitutes, I have heard good things about Vegusto, and plan to order a started pack soon, to give a selection of their products a try!