Peter, please keep on telling -- reading your story, I recognised my own story several times ...
I very much understand your doubts about a sudden decision to marry ... It's very unusual for us Western people. But on the other hand, there is never a guarantee that everything will be right.
With my former wife, we lived together for 2 years before we married. And the result? Unhappiness, and divorce at the end.
I met my future wife only for a week, and I made my decision. A big YES. Whether it's 2 years or one week before you marry -- it's always an adventure, you never know what happens in the future.
The difference for me is that with 43 years I know much better who I am and what I want, and I can appreciate her much more than 20 years ago.