Same here. I never got into the whole HL series. It wasn't from a lack of trying though. At first, I played 1 and 2 both at least half way through and still couldn't like them. I kept waiting for these, very much hyped, games to "get good" but they never did. I did finally play them both through, but it was forced and out of boredom. Admittedly I played them well after they were released(steam package sale, years after release), so that may have had a big impact on why I felt this way about them. Though if that was the case, I probably wouldn't have liked portal since I played it well after it was released too(free weekend deal about a year ago) and subsequently, Portal 2. I loved both of those and still play them ever so often. Amazing games.
Someone said earlier they wished they would have worked on HL more and not made stupid games like Portal. I feel the exact opposite. Everyone is different though, and Valve knows this. I trust that they will work on several different types of games and not focus and pin all their hopes on a single one, like some would want.