It can very person to person, and other things can affect it as well, ie, medications, your health, and stress. Also, being turned on also seems to make a difference.
It's the same with GG's; everyone is different. One example is one of my ex girlfriends (GG), and she had a problem with self lubing. She had to use lube or it would hurt, since she didn't produce enough on her own. There's a lot of women like her. There's nothing wrong with lube (it can be fun!).
As for myself, I self-lube, but it has varied depending on what medications I've been on, stress in my life, and if I'm turned on.
As for dialating, I will usually use a small amount because dialating isn't really a turn on. Unless I were to be using a toy or being with someone... but as for the hospital ones, they don't get me in the mood. LOL
As for douching after, one should have to or need to do that -- douching can be very unhealthy. Granted, in the first couple of months you will, because that's what the doctor recommends, but after 3 months most docs say don't, unless you're told to.
Why? Because you have vaginal flora that keeps your vagina healthy and helps fight off possible infections (bad bacteria or yeast). The healthy flora can also help with self-lubrication, because your vagina is healthy.
But, again, it will vary from person to person and it can vary depending on other factors (like meds). It's the same with GG women, some are drier than others and some are wetter. So, if you end up needing lube, it doesn't mean that there's anything wrong or that you're vagina isn't working correct.