I have a love hate relationship with my high functioning autistic brother who had a very successful career. He was not diagnosed until he was mid 50's. I speak from my own experience here and I know I will get flamed for this but, there are two perspectives for this. And I will start here by saying that every autistic person is different so this isn't a carte blanche analysis, its just my experience with my brother.
We always knew he was different, his way or the highway and my parents took the course of least resistance and gave in, it drove me mad as much as I loved him. I felt pushed out as if my needs/wants did not count. He had a major meltdown that landed him in major trouble in his mid 50's and that is when he got his diagnosis.
I now understand that he is wired differently to us, its not him being self centred but what he needs and how is brain is wired but his ability to focus on one thing only and push for it in a variety of ways is impressive but also dismissive of our feelings. And its that attitude that got him the amazing career. But in saying that, now he has the diagnosis, he needs to appreciate that there needs to be some accommodations on his side too, its not his get out of jail free card, and its not always about him, because other people have feelings and needs.
It takes both sides to adjust to the diagnosis, you need to understand that they have a right to their choice too and their rights/needs always being pushed to one side does become very unfair and frankly waring. My brother can't help that he is wired differently and after his diagnosis, I can certainly understand and appreciate many of our life incidents better now, but he doesn't seem to have the same ability to reflect.
The problem is that he seems to make these allowances at work, which is very much working on a one to one with other people, but when he has an emotional connection with someone (like family), he doesn't seem to be able to interpret things in quite the same manner. Again, I know he can't help it, but he has acquired coping mechanisms since childhood that need to be re-addressed now he has his diagnosis, in the same way we need to revisit stuff too.
Your diagnosis is also their diagnosis, as in you need to work together and if you are simply telling them...and not working with them, considering the changes they have had to cope with, it will create resentment.
That being said, your family obviously love you as you are and now know your diagnosis and its a voyage of discovery for all sides. I would encourage you AND your family to join support groups to reassure you are not alone with this and that it is part of the diagnosis and there are lots of others going through this and you can support each other.
More and more people are being diagnosed with this type of condition and I think its because we are at long last accepting that not everyone is wired the same way, which isn't a negative thing and we need to rethink societal norms because we are all different in some way.
I don't think I am explaining myself well here but hopefully you will understand some of it.