I see it as a nearly literal translation of the English notion of:

“They only like/love you [even] more for that/because of it”

I see the “en” as meaning “for that” or “because of it,” where the “that” or “it” is something you’ve done or said (or a character trait you have) that has made “them” love or like “you” even more than they did before, but I don’t see any implication that their affection for you has reached the point of being excessive.