Heavy stuff man, but like I said before, you are handling it with class.
I think you have a great attitude as far as your D17 goes. Obviously, her getting pregnant at this age is not what you would chose. But it has happened, and she needs her dad. I am glad you are giving her that support.
Now, as far as pushing forward the D, I agree with what SC said. Unless D is what YOU really want, NOW, I would leave it be. I would not use it as a "tactic."
You can show her you are not simply waiting for her by continuing to move forward without her. Continuing to work on yourself and doing new things.
IMHO, unless there are legal or financial issues, that put you at risk without the D being finalized, there is no benefit for you to push it. She wants it, let her do the work.
Just 2 pennies.
BITS
Happiness is not something ready made. It comes from your own actions.
