My story is somewhat different. My maternal grandfather was slick as a boiled onion for as long as I can remember - his was by nature - no shaving back in those days. I think he was 45 when I was born. Even though I set through the same biology classes as you guys, it never dawned on me that I would get MPB just like my grandfather.
I started noticing the thinning in the back in my freshman year of college - this was 1983. My barber pointed it out to me. I think it was at that time that I made the connection with genetics, maternal grandfather, etc.
Anyway, I panicked. I was always known in my high school class as the guy with all the curly hair. I was 19 and panicking. The girls loved it and I always had to have it fixed just right.
At the age of 20, my barber suggested I go the toupee route. I bought into it. Instant hair - all problems solved. So here I am going through college and graduate school worrying about my hair. I spent the next 23 years hiding behind the rug.
I went sly last week (with major help from this board). My advice to you is accept the thinning, balding, whatever. It is a part of you. People don't like you because you have hair. They like you for who you are on the inside.
Bottom line - embrace the change. My only regret is I didn't embrace it 23 years ago.