I'm sorry, then, that your friend did such a crummy job when it comes to boundaries with this and you. I'm also sorry someone who is your friend was unaccepting. We can certainly talk about if you still want to be friends with this person, or if you want some help talking to them about how all of this went. Personally, if this was my friend, I'd want to at least have a talk with them to point out how they disrespected by boundaries, and to ask them to do better next time, and to tell them I was hurt by their reaction to my coming out, and would be asking them to do better in that regard, too. I can't speak for you or your friend, but I want to be a good friend to my friends, so however uncomfortable it can be, I'm always glad when they point out when I could be a better friend to them, because I always want to be.
I'm not sure where you're encountering -- separate from this bit with your work friends -- people saying that ace/aro isn't or shouldn't be part of the queer community, but if you're running into it a lot, might be time to fine-tune the community you're part of so that you're choosing people and groups that actually ARE community for you. It's not our community, after all, if it doesn't include us or we have to fight nonstop to try and be part of it. Our communities and those that embrace us and accept us and include us.
Never doubt that a small group of thoughtful, committed citizens can change the world. Indeed, it is the only thing that ever has. - Margaret Mead