Doni, you are right, there is no passage of not-marrying in evil times. I have no idea why I tied that up in my head to the child thing.
But in the Athrabeth, isn't the whole point that Finrod's brother can't marry the mortal girl because there is a war going on, and the Noldor don't marry during war? I have never opened Morgoth's Ring or Peoples of Middle Earth, so I am sorry if this reference is confused.
I think we can conclude: Legolas was not married at the time of the Quest, because none of the other members of the Fellowship were married. Both Aragorn and Sam had girlfriends waiting for them, but no one was married.
Legolas was not married (and then widowed) prior to the Quest, because that would mark him with sorrow, and he is not so marked.
Legolas did not marry between the Quest and leaving for Valinor, because the event that allowed him to part with Middle Earth was the death of Aragorn. If Legolas had married, his marriage would be a much more important relationship that his friendship with King Elessar, and would serve to tie him to Middle Earth. (Of course, any hypothetical 'wife' would have taken ship with him, but his desire to build a ship would be lessened, I think).
Legolas may have married after reaching Tol Eressea/ Valinor. Oh, and Gimli, Bilbo and Frodo do not actually go to Valinor - they just go to Tol Eressea.
So, to get back on topic

See how easy that is? Of course, that leaves Faramir dying and/or miserable, but oh well.