I had a similar experience with "Ulysses." Forced myself to start it, continued to read it, finished it, had about 30% comprehension. Sheesh, it was humiliating, especially because it's supposedly a great book.

[Fun fact: When I was about 12, I heard it had been on trial for obscenity. So I went down to the library, found a copy, and started looking for the dirty parts, seeking titillation. Imagine how well that worked out...]

Circe is waaaay better imo. More fascinating, maybe because it's a less-told tale. And more beautifully poetic. I read it first and was knocked out by it. Achilles was meh.

[Edit: Not knocking your appreciation for Achilles. Just saying, if you liked Achilles, you'll really enjoy Circe.]