It just makes me mad, you know? They need to be educated, but if I came out, they wouldn't respect me enough to listen to what I have to say. smh.
That's why I don't think a big announcement is the way to go. With everyone else around, people tend to not want to go against the prevailing group opinion. Just let things slip out occasionally. Then, as one person starts to figure it out and, hopefully, asks, you can address it with them alone. Or, you can take mom aside and speak calmly with her. Give her time to digest the information and maybe she'll help you decide the best way to address the issue with the rest of the family. Maybe some family members, like grandpa, would be better off not knowing.
Baby steps will probably work best in this situation.