The intimacy and intensity of Domina / sub sessions and interactions can understandably generate that phrase "best friend" from sub to Domina even though, especially in the beginning, the relationship is by nature transactional.

In my experience over a lot of years and more than a few Dominas, I became friends with at least two of my longtime Mistresses. We confided in each other, I helped them with some marketing in their vanilla careers / businesses, we went out for lunch or dinner socially. Of course tributes were still paid for (I made deposits in their checking accounts) but I received special privileges such as sessions in their apartments. They weren't clock watchers either. Yes... I've been very lucky.

One retired from the scene and, eventually told me not to contact her anymore which was difficult but I respected her wishes. The other Mistress is still active but under-the-radar and does not advertise anymore. We still session a couple or more times a year and keep in touch.

As for the addiction question, with both I've been in the deepest subspace ever. At times I wallowed in it, to the detriment of part of my day-to-day life. On the whole I've valued both friendships.