Let's break down Silvergun's sentence shall we?
First part: "I just can't bring myself to hate the Rays"
= From this part of the sentence, we can gather that Silvergun may find the Rays to be a likeable organization/team. As much as he wants to try and root against them, he simply can't because there really isn't anything to dislike about that franchise from his view point.
Second part: "The rest of the AL East is so easy"
= From the latter half of the sentence, Silvergun makes it apparent that the rest of the AL East is easy to hate in his mind. It is rather simple to come to this conclusion if you bridge the first half of the sentence with the latter half of the sentence.