No Gamer Is An Island. Or: Why I didn't like Half-Life 2

[Combine 017]

You really arnt alone for that long in HL2. You might not be with the same person very long but your not alone. The only parts where you are completely alone is in the boat/car levels(which you said they were the ones you liked) and in Ravenholm(and even there you have Grigori checking up on you). Otherwise your with Alyx, Barney, Kliener, Eli, Judeth, D0G, a swarm of Antlions, or a band of rebels.