Pariah3j wrote:IANAL but I like to pretend I play one on TV and I stayed in a Holiday Inn Express once
From watching various legal TV programs and such - from what I understood, there are 2 types of gifts legally speaking. There is a conditional gift (ie an engagement ring, it is contingent on you getting married before the terms of the gift are fulfilled) and there are 'normal' gifts - these technically should have no strings attached to them, just because the person wanted you to have it - this would be christmas/birthday/etc type gifts. Now the case I saw where this was explained was not in Texas, and it had to do with an engagement ring.
Assuming she filled out the NICS form as it being a gift, it should be easy to prove it as such in a court of law. The other thing that I would think would play a part in court is, she gave you the gun 6 years ago, if she thought it was hers and not yours, why did she wait this long to try to take possession back?
But as others have asked, is the gun's value (sentimental wise or otherwise) worth it? Ex Gfs are like terrorists, best not to give into their demands usually, but it might be worth it in this case.
You don't say whether the firearm is a gift on the 4473, only that you are the actual buyer. Which if you are buying it to give away, you are! So the gun shop paperwork is not going to show anything about someone's ultimate intent for the firearm.