You poor sweety I think they are all being so selfish... you are so not being unreasonable!
All you need to worry about is you, Shel & your precious baby. Make sure you stand up for yourself and set the boundaries now. And I agree with the others - you don't need to tell them when you go into labour unless you want to!
This is SO not about them... they will get over it.
As for the natural birth - it is SO doable! Just because its not what they're used to does not mean that youre being naive! I think you are doing the right thing
All the best darl