UX in games - includes emotional reactions?

Warning: This post contains major spoilers for the ending of Half-Life 2: Episode 2.

One of my hobbies is playing video games, and as I've become more and more interested in UX and HCI I've wondered how much of the video game experience is considered the user experience.

Two games I've played in the last few years stand out in my mind. One is Alan Wake, a survival horror game about a writer who's wife is kidnapped by a supernatural force and his attempts to rescue her. At the beginning of the game, it's explained that Alan's wife suffers from a fear of the dark. The couple arrive at a lakeside cabin, and while Alan is outside the power is cut to the cabin and his wife begins screaming in fear.

At the time I played the game I was engaged, and I could relate completely to the situation. I mashed the sprint button, running Alan back to the cabin to check on her and as I did I could feel that I had become tense and anxious. The game had triggered an emotional reaction in me, and I had only played it a few minutes.

The second game is Half-Life 2: Episode 2. In the game's final scene, Eli Vance is grabbed by an alien creature and murdered on-screen while the player's character is pinned to a wall, unable to move or stop the alien.

I was shocked at the death of the character, but my wife was choking back tears. She told me that she had liked the character of Eli because he reminded her of her grandfather, so his death had a much greater emotional impact on her.

In both these cases, life experiences caused a dramatic scene in a game to have an even greater emotional impact on my wife and myself, the players. To me, that's one of the highest goals a game UX designer could hope to achieve. Because these two moments triggered such emotional reactions within me they remain two of my favorite gaming moments. I see no reason why emotional responses to games should not be included or considered part of the user experience of them.