I'm not sure that this will help your decision. I was recently diagnoses (June), and have been struggling with the same decision. Close family and friends new that I was struggling with symptoms that were being followed by a Neurologist, so that made it less of a challenge to tell those people. My major struggle is with work. I have had virtually no visible symptoms until recently, when I had an exacerbation. I feel strongly that my chaotic schedule at work over the last few weeks (60+ hours/week) was a contributing factor to my having a huge setback. I had been doing so well with my adapted 'MS routine' (meds, exercise, alternative therapy, diet, vitamins/supplements, etc) until the crazy hours ran down my body, and caused me to catch a stomach bug that was THE worst stomach bug that I have had in over a decade. That seems to have caused a domino effect and now I have lost the feeling in my right hand and food, had a significant increase in spacisity, loss of energy, etc.
Well -- didn't mean to blab on about ME. I just wanted to share enough to let you know that I completely understand why you are struggling with the decision of who to tell. To use my situation as an example, I don't think that anyone should HAVE to share personal health information with ANYONE. However, the question that I ask myself daily (lately) is this: Will telling someone/anyone help to limit my exacerbations or help to manage my exacerbations? At the end of the day, we have to protect ourselves and do everything that we can to manage exacerbations.
Explaining symptoms is the least of my worries. Example, leg spasms: Why are you limping. Oh, I have been having leg cramps lately, and my leg just stiffens up when I sit too long. Then, people usually drop the subject because you have given them a plausible answer. Another example, vertigo: Do you mind if we take the elevator (instead of an escalator), I have a touch of vertigo that has been bothering me. "Oh, really, what is it from?". Oh, I have always struggled with ear problems that have caused balance issues .... some days are better than others. Again - plausible answer, dropped without further discussion.
Granted, Optic Neuritis can more of a challenge to explain, but you get the general idea.
I have seen SO many people respond to like threads saying, ABSOLUTELY NOT, don't tell. At the end of the day, it is your decision and you have to ask yourself if the 'don't ask, don't tell policy really works for your situation'. Everyone has a different life situation (family, friends, work, etc) which translates to -- it has to be your decision, based on your life.