There is, IMO, absolutely no hint throughout the time that Kes is on Voyager that she and Neelix have gone much beyond hand-holding. Sorry, Kimc, but I just don't see it. Sure, it's possible, but if so, it's one of those things that the writers chose not to show us or even hint to us.
Well they did make out in the mess hall while the rest of the ship was dealing with being inside a nebula.
The point I've been trying to make though is that you can't apply human sexuality to an alien species like the Ocampa. Humans generally go through puberty before becoming sexually active. Who is to say things don't work differently for Ocampans?
Personally I don't care either way. It just strikes me as odd to apply human standards to aliens, that's all.