You've got other songs...Just let it go...I say this because I have been screwed in the past and, at the level it sounds like you are at now, you're probably going to look back at that song in five years and think it's so small amongst the work you've produced by then.

I think it's great some people have luck with internet collaboration but, for me, I have had bad luck so I think it should only be done with extreme caution...

BTW, was the person you wrote with a minor? Because if that's the case you may not have been able to make a contract with her in the first place...Wow, though, too much of a headache