Tiggy- very powerful, valid, relevant thoughts I know I have myself. DH and I don't have a child so I do know I definitely want that. But the thought of the exhaustion, no longer being able to do what I want, regularly crosses my mind. As does my age when then child is ten and twenty etc.
You've had way too much happening, which normally wouldn't be going on which is a big part of how you are feeling. I for one think it's great that you are thinking about this stuff and maybe for the first time know that you will be fine if this doesn't work. Sounds like you still want to go ahead but recent craziness has given you a more realistic perspective which can only be a good thing. Just take some time to process it all xx