The most breakup-y breakup was Kes and Neelix.
Kind of, the breakup we saw was a malevolent entity that had possessed Kes's body dumping Neelix. IIRC, there was a very small deleted scene an episode or two later, where Kes tells Neelix that she decided the murderous alien who had taken over her mind had a point, and they should see other people, but since it was never included, I remember being very confused by why that stuck. "She was possessed, they all know she was possessed, why are they acting like they actually broke up?"
Other ships could still follow them and follow their warp trail.
Like when at the beginning of the episode, when Vadic was complaining the Titan was laying down false warp trails, dropping a decoy probe at the end of the line, then doubling back and going into another direction? Once Titan builds up a lead, eventually, they'll be able slip out of sight for long enough to put a fork in their warp trail, then another, then another, just like they were before.