Why did it "take the wind out of [your] sails" when she mirrored your feelings about the evening?
You declined the invitation in...good for you.
The "why do you want to x now?," interesting question, I get that so much.
You feel that you haven't been a priority, I feel the same way and somehow even though my life has been revolving around H's needs, career etc. somehow he feels that way too. Maybe my resentment permeated our interactions so much that he couldn't experience the loving and supportive me that was there so much of the time. Not sure about your sitch but it seems that it is a cycle, you've resented being second fiddle for so long and she experienced that as rejection...not sure, just speculating.
I think being open to the "no future" prospect is the ace in your pocket. Still, from my vantage point, the future seems very plausible.