Honestly, she has dropped some very serious issues on you which are dealbreakers for many. You asked how she could have dated and seemed fine, or thereabouts.

Sometimes people stay out of fear of being alone, fear of having to start afresh with a new person, or hurting the person, and in the process they lie to themselves and tell themselves they are just nervous when having doubts during their engagement.

They fool themselves into thinking if they can act the part long enough that they will become the part. But like all plays, the curtain eventually comes down

Sorry you are experiencing this. But you have youth on your side and no children involved.

Now it is time to not let fear rule you. Yoi can't make her happy nor should you stay in a love deprived marriage.