She HAS been dating Scrubs' Donald Faison forever, but just what was newly single Nick doing with his former fling (and ex-wife's BFF) Cacee Cobb yesterday?

The pair met for lunch at Casa Vega in Sherman Oaks but left the restaurant separately. Now that Nick and Vanessa are dunzo, is Cacee going to dump Don to hook up with the man she supposedly sided with in her BFF's divorce?

Course, Cacee claims she has "the best boyfriend in the world, I would never!", while Nick just said nothing!