Best written Batman love story in the comics is without a doubt the Silver St. Cloud run. While Silver is relatively generic, she is at least a strong willed, fully realized woman who is an ostensible equal to Bruce Wayne. And it's a good story, straightforward and poignant. Silver actually has the backbone to make a choice and stick to it when she leaves, making a point of the sacrifices the hero makes for his war on crime. (The less said about the horrible sequel published more recently, the better.)
While Selina Kyle is often played as if she is Bruce Wayne's equal, for the most part the love stories involving her are bad. There's a severe tendency to undercut either her or Bruce Wayne's characters - that is, Selina either becomes a waffling good girl, or she gets played as criminal with an adolescent fetish for making Batman chase her (what are they, on a playground?). Or Bruce Wayne gets turned into an angsting wuss bent on long talks about "our relationship" (*coughHushcough*).
Talia started off as a feminist's nightmare, living only through either her father or her "Beloved" (is there a nausea smiley?), with no will or mind of her own. I understand that has somewhat been remedied but the divided loyalties schtick is only powerful if it's in a shorter story. After years and years of supposed divided loyalty, you just want the woman to quit whining that she can't make up her mind.
Rachel Dawes was probably the best of all Batman love interests though. With a strong backstory and an actual life of her own, she's the one character it makes sense, without a doubt, that Bruce Wayne would be in love with her (that is beyond the usual male fantasy fulfillment of she's HAWT!). She is dedicated to justice for her own reasons, she pursues her work with vigor and dedication, she makes tough choices to move on with her life and doesn't wring her hands over it, she's courageous and she is both loyal to Bruce, and willing to stand up to him. I was dubious when they introduced the "child hood sweetheart" angle, but it was pretty well handled in both movies.