Congratulations Marmalade, and here begineth the fun side of life
, party party party.
It's so positive to hear that you have pushed forward and taken the plunge, especially with how worried you have been about it all.
I'm honestly not sure what teh best way is to drop it to your parents, maybe take your friend with you when you tell them so you are not alone, just incase there is a slim chance they go mental?
Just be ready for the guilt trip, the recriminations, the threats, the emotional blackmail. It will only be hard on you if you let it get to you, don't let it get to you.
Be firm that you are moving out.
Good luck Marmalade.