As far as I'm concerned MC is a disease, I'd use this definition in support:
"A pathological condition of a part, organ, or system of an organism resulting from various causes, such as infection, genetic defect, or environmental stress, and characterized by an identifiable group of signs or symptoms."
MC results from a genetic defect and gives rise to identifiable symptoms.
Many people have MC and never realise it, the symptoms are so slight, however, for some of us the impact is more severe. My MC is serious enough, even with relief from using Mexitil, that I am banned from driving on health grounds. I am not particularly strong and suffer from bouts of muscle weakness, especially in the arms.
I have I learnt to live with MC? I suppose I have but then it's not like I was ever given much of a choice. It has never made me feel any better being told that it's not the worst I could be suffering from; it's bad enough thanks!