a) One in which there are secrets, and Emmeline can never know who Remus actually is. Thus Remus isn't a particularly nice guy, seeing as he allows himself to be with her regardless, setting aside his guilt for what?
b) It's the real deal, never to end, the one thing that keeps him steady through everything. In which case, what brings it to an end? Is it the fact that Remus is a werewolf? If so, then Emmeline is a bit of a bitch. Because some things are black and white; Remus is a good man, werewolf or not.
My problem with Remmeline is that Emmeline is still alive by the time the Order of the Phoenix is re-established. It's awkward. Tonks is meant to be something unique. I always gathered that it was the first time he allowed himself to commit to a person fully. Sure, there may have been other women, women he loved from a distance or who kept his bed warm (to put it oh so politely), but I imagine it's a tricky ship to ship. With that in mind, I can understand shipping Remus with Marlene or Dorcas. At least then it leaves him a broken man, unable to trust himself to feel when it's only going to lead to tragedy. But even that is problematic, for reasons see my previous rants, filed under the Wolfstar link on my page.
I can't imagine people would roleplay Emmeline as someone who turned away from Remus when she discovered that he was a werewolf. So what happened that meant Remus and Emmeline didn't stick it out? Did he push her away? I can imagine that, but maybe that's why Tonks trumps Emmeline; she had the perseverence that loving Remus required. If I'm missing something, please enlighten me. This is just a rant, because I like to rant and I happen to spend a lot of time thinking about Remus. This is probably an unpopular opinion, but the moment you decide to ship Remus with Emmeline, or Dorcas, or Marlene, you take a leap away from canon and Remus' character is compromised.