After 2nd PUC exam you would have waited for 3rd PUC exam when you would have almost proposed to her but then you would have waited for the 3rd FUC exam which would have been very critical for you.
So stop deluding yourself. You would have never said anything to her. And the way she vanished it is clear she never gave you a dam, so even saying it would not have fethced any result
Alas! no true or false love knocked my door till i fell prey of an arranged marriage. Even after 10 years of my marriage i am feeling happy that unfortunately deviates my mind to listen to my doors for any possible knock. Anyhow, wish you couple a happy life.