Even as someone who didn't really get into PC games until I was in college, the Half Life games were almost single-handedly responsible for shaping my taste in games. Even as I played Ratchet and Clank and later Halo at home, I remember going to friend's houses as a little kid and watching them play the first Half Life. I remember being initially weirded out by how fast Gordon moved, but growing to love it, and the game, more than I ever did Halo. HL2 was the first FPS I ever owned on PC, and as I got more interested in playing a wider range of games, I came to see how unique it was. I don't know of any modern games that manage to be as simple as HL2 was while still being incredibly fun. Sure, it wasn't perfect, but it's about as close as I've ever seen a single player FPS get. Even the Doom game that came out last year had to come out with a minimap, just in case, a dumbass little upgrade system to pull you out of playin a fuckin game, and more unskippable cutscenes than HL2 ever had.
Honestly, I haven't read the ending yet, and I don't know if I want to. Half Life was never really about the story, it was about the neat little tricks Valve pulled to keep you invested in hitting buttons, and to keep you learning as you went. How could I have guessed back then that Valve would wind up fucking over the two games of theirs I loved the most?