I wanted to cry. (Depressing reasons as to why I wanted to cry, but let's glance over that)
I messaged my friend something along the lines of "I want to cry. Give me a show that will make me cry."
He responded with one word: "Clannad".
Well, I had only seen 5 episodes of any anime ever at the time, so I was hesitant to jump in at first.
I watched the opening of the first episode, and I immediately related to Tomoya, and I watched on into the night.
At 2 AM, once Fuko's arc had ended, I can easily say I fell in love with Clannad. Although I did not cry at that time, my eyes were wet. I finished the series in about 2 days, including After Story.
I branched off to a couple other sad series, but when I found that Key was responsible for Clannad, and had other works, I quickly watched as many as I could.
As of February 16, 2016- I have now seen every Key anime, plus planetarian. I'm working on the Clannad VN right now.
So, basically, my friend showed me.