Needing major advice....

Good Evening.  I am hoping that someone will be able to relate to my story and offer me some major advice.

Here is my story:  I have been with my husband for 30 years (high school sweet hearts).  About 2 months ago (after speaking with a friend with ADD), he decided to go see his PCP for what he is recognizing as a long history of "inattention".  This was news to me and I was pretty confident that he didn't have ADD.  I encouraged him to follow up but really didn't make much of his appointment.  This led to a neuro-psych eval and ultimately the diagnosis of adult ADD.  I was SHOCKED and BLIND SIDED, and for some reasons I cannot understand, felt betrayed.  We have had an amazing relationship over the past years (ups and downs like most people), but I would describe our relationship as "rock solid"; I don't see ourselves, our relationship, our history as what I have been reading in the many many articles, books, blogs, etc that I have read.  Since he began this journey I have had an amazing amount of anxiety (new, lost 12 pounds in 3 weeks), and have been in emotional distress.  I have read every single piece of information I can get my hands on at all levels (lay terms and medical - I'm an NP), but everything "speaks" to the spouse or the relationship that is in distress because of ADD; this was not my situation.  For reasons I cannot describe, and praying that someone has gone through this before and can tell me their story, I am absolutely terrified of him being treated with medication.  I am afraid medication is going to change his personality, our relationship, our life - a life that I love.  I have committed 100% to supporting him in this journey and recognize that this is not about me - but this has thrown me into a whirlwind of emotions that I am having a very difficult time understanding where this is all coming from.

Would really appreciate anyone who would be willing to lend me some advice if they went through something similar, and how are you now?

Thank you for taking the time to read,