The dating scene in SF is hellish. Having a few good friends in the city, and having spent a lot of time there myself, I know there's really no escaping a breakup there. It's like a shadow you can't shake. A shadow that likely knows everybody you know or will know, and probably already fucked a good number of them, or will someday, and everyone you want to avoid is but a stone's throw away regardless of what neighborhood you call home.
You're probably going to end up breaking a lot more shit from a lot of other ex's before your time in the city is through.
Beautiful city, though. And a great weekend getaway.
P.S. Sorta off topic, but in the 29 years I've been on this planet, I don't think I've ever come across an area of the U.S. as heavily populated by desperate, easy, attractive single women as the Marina District. Ridiculously easy pickin's.