I'll bring the booze. OP could use a lot of it.

No, he is not at fault at all. Even if he left it out on his desk, box open for the world to see, he did NOT give it to her, so she is completely at fault for assuming it was for her. From the word "found" in the FML it certainly implies it wasn't left out on display either, rather that she's seen a box and even though it wasn't her property, decided to open it and look inside and jumped to the conclusion it's for her. Engagement rings are almost always none returnable, and to sell it for a fraction of the price/throw it out would just equal throwing a bunch of money away over someone who hurt you, which just adds further insult to injury. There's also a pretty good chance he isn't emotionally over his ex, considering he felt strongly enough to want marriage so letting go isn't that easy. I can definitely see the economical reasons for keeping it for a possible future relationship if it gets serious, although i'm sure the female might get offended if she ever found out she wasn't the original intended recipient and it wasn't bought with her in mind.

You also have to realize that there are people that the rings are meant for that they find it on their own when doing something as simple as cleaning, so instead of having gotten rid of the ring before even having started to date someone else, he is at partial fault as well. And in all honesty, having to keep things as low amount as possible when having gone through something big, especially if it's something like a ring, it's usually better to keep it actually fully away and way completely out of sight to try and get over it since seeing something that significant will only bring back the painful memories. And it shouldn't be that you're "sure" that the girl will get hurt, because the girl WILL get hurt if something like an engagement ring was originally meant for someone else. When it comes to something major like the rings, we girls tend to want something originally intended for us - Period.

How do you know he wasn't keeping it to pass on to a daughter in his future? Making the best of the shit situation, and not wanting to part with what is most likely an expensive ring? I'm sure THAT girl wouldn't mind the ring not being bought specially for her... because that would be a creepy notion given its intent. Not every girl wants everything to be about them, not every girl desires marriage and not every girl should get excited at the prospect of engagement after three weeks. You don't even know the guy well enough to be aware of his past almost-engagement, never mind enough to commit to a marriage with him.

I'm sorry, but i really do not agree. It is completely normal to keep items from past relationships. I kept a perfume, locket and a ring from my ex fiance, not because i was trying to hold on to memories, but because he was a cheap bastard and despite how generous i was to him they were the only things he ever gave me, i even had to buy my own engagement ring with that guy. Throwing out something of value is pretty pointless, it's just cutting off your nose to spite your face. As for the girl would definitely get hurt, not really. Most engagement rings look virtually identical, why sell/get rid of one just to buy something that is basically the same? His ex either never got given the ring, or didn't accept it, so she never owned/wore it, i personally don't see the big deal in him giving it to another girl. To me at least getting engaged is so not about the ring, that's just a physical sign to others that you're taken. I wouldn't care if i got one made out of silver paper, plastic, or one of those haribo sweet rings, or even no ring at all. It should be about how you feel about each other and wanting to spend your lives together, if the ring is that important, she's got her priorities way wrong.

not really scientists usually go early June to late July, not near the end of August.

1) It was a joke. 2) June/July is the dead of Antarctic winter. I have actually worked with people in the Antarctic program. For the fairly obvious reason I just stated, most people go around October and come back around April, unless they are either truly dedicated it have some research that requires -100F outside temperatures.

KINDA!?!?!