So I haven't posted in a while cause I feel bad cause my transition went so fast it hasn't been a year yet since I started and I have already transitioned completely socially. My name is legally changed next month and my surgery date is set. However I'm dating and now unofficially engaged to the most wonderful man who both knows and is fully supportive of my being trans. However of his family he is the only one who knows and I wanna keep it that way. His family is great and since I pass so well no one suspects a thing. However with the fact that our family's are coming together soon what scares me is the fact that since I have transitioned so quickly I have family members who still don't always get everything right and worse yet some that are still being stubborn. One is even going so far as to threaten me with crashing my wedding so that everyone knows that I'm trans. Please help me I'm so scared that this beautiful life where I am finally the woman I always should have been is about to be torn down around me. I feel threatened and like I need to defend myself against my own flesh and blood.
You have few options. You could have a wedding excluding most or all of your own family, you could hire security to stop unwanted guest but the word may still get out when people leave or you can tell your mother in law. About the only way to remain stealth is tell a very limited number of people or tell nobody. This is why people who wish to remain stealth start an entirely new life away from anybody who knows.
tell the ones who threaten you that you'll have security and they will be arrested or just tell the ones you know that accept you where the wedding is going to be or have a civil ceremony in a court house and a private one at some other time. I don't know your wedding plans, but you can just keep it very simple at someone's house. You can do this , don't let the clowns win.
I don't know if it would help, but if you do the legal one before the family one then in the worst case if it blows up you'd still be married. ie do it in the morning or the day before.
Any chance of getting a restraining order?
I would inform the local police that someone has threatened to disrupt your wedding. If any uninvited guests show up, have them arrested for trespassing.
I also think living a stealth life is very stressful. You'll feel a lot more tension if you let people know you are trans. Keeping a secret uses a lot of energy (as you can see by the concerns you post here).
This is something to talk with your fiance about. It's his job to make sure his family treats you with respect, regardless of whether they know your history.
You DESERVE to be treated as the woman you are, even by people who know you're trans. Your fiance needs to understand this, and he needs to make sure his family treats you with the respect you deserve. If he is pressuring you to hide your history from his family, that is worrisome. He should be trying to make life easier for you not pressuring you to keep a secret.