I'm like this with pretty much all games now. I just don't see the point playing through games again, no matter how amazing they were. This may be partly due to not having a lot of free time at the moment, but also not wanting to soil the original experience by noticing potential flaws which may ruin the overall experience. I've been meaning to start Shadow of the Colossus again, but I don't think it'll live up to my memories.
Once the main game is done I either stick with the multiplayer or move on to the next.