What are things you have learned now that you wish you knew when you were younger?

You can calll then regrets if you like. . .
First thing. . .it would have to do with past relationships I had with people i no longer have contact. there are so many things i wanted to say but never go around to say, even though i had many chances to say it.
One person stands alone on this one and i still miss him dearly. And even if he would be sitting here with me, i still wouldn't know how.
Second would have to do with the choices i had made when I was in school. If i could have done several things differently, that would be paying more attition to things i've been tuaght without my LD getting in the way.
Third, I wish i was more outgoing when i was younger and that guys my age (12-18yrs) are nothing more than human and nothing to be feared. We all have insecurities.