The hardest part I find about having a child is the lack of alone time. I'm a very solitary person - I need time to myself to be able to function properly. My favourite times are when I'm by myself - many days when I work at home I don't even have the radio or music on - just blissful silence. Even when I'm with close friends or family I need to wander off by myself for a little while to regroup. That's one reason I couldn't do teaching full-time - as much as I love it, it's very draining for me to be around people so much. I prefer my own company, and that of my online friends, as I can choose when I want to be sociable.
Unfortunately I've been 'blessed' with a child who doesn't like to be on his own for any longer than 10 minutes, who needs constant stimulation and loves noise. I have 3 days/week where he's at preschool which is my sanity saver - unfortunately this term I've been so flat out on those 3 days with training, my course or meeting with clients that I haven't had much alone time lately. And I'm really starting to suffer from it.
I'm so hard to explain how I feel to people - I think only people who share my 'affliction' will understand. My grandfather was a bit of a hermit - I think I've inherited it from him :)