Cangie - BTW, since I don't know all the rules and niceties of social etiquette, would it be o.k. to throw myself a party next year?
It is perfectly acceptable. My wife even looked it up online. For you, I would highly recommend using your story to help promote it. People will rally around you if they know you've never had a birthday party. They will feel good because they're doing something very rare and unique and meaningful. You will feel good because you're felt and seen and heard. Make it whatever you want, and have fun with it.
Tips: Again it may be the marketer in me but I realize that people are busy and need to plan ahead. So we made a Facebook event and added everyone we invited to the event about two months in advance. Then we talked about it as we saw people to keep it fresh in their minds. As we got a few things together for the party like a venue and cake, we'd tell everyone more details on the event page which again puts it in their mind. My wife had invitations printed and we made sure that everyone had one about 2-3 weeks before the actual party. Finally, the weekend before I sent out one last notice on the Facebook event page, one final reminder and how much we hoped to see everyone there. People are busy in the summer with kids' baseball games and church carnivals that they help run and vacations, etc. So we made sure we kept our event in their minds without becoming annoying. Each time there was something different that would pique their interest.