Sharing news of diagnosis

I was diagnosed with Autism in July, aged 39, and though this diagnosis has been a relief, and has helped me better understand myself and my struggles since childhood, I have shared this news with only a very small number of people. I have not told my parents,  and I have only told one of my friends. Only my husband and my brother knew I was being assessed, and so the news is likely to be a surprise for everyone else.  I would like to share this information more widely, but I am worried about how people will react, and whether or not the information will be helpful or harmful to our relationships/friendships, and how they see me. In some cases such as with my parents, I am worried about them being dismissive of the diagnosis. Sharing news of a diagnosis of something like Autism is also not an easy thing to bring up in every day conversation, and so though I have planed to mention it on a number of occasions, I have just not felt able to.

It would be really helpful to hear any advice or experience of overcome similar worries or mental barriers to sharing the news of an Autism diagnosis.