Half of me wants to work on us and the other half says screw it.
Which half wants what?
Why has the decision fallen to me?
Very good question. And there's always the risk that, in fact, you're just rescuing. On the other hand, I don't think you can get a clearer signal than the cessation of begging -- which, by the way, is why it has fallen to you.
And, while this -- She said if she comes home, she would like a clean slate and would like the opportunity to work on us together -- sounds reasonable, your reaction -- How could I ever trust her again? -- is the $10,000 Question. There is the Schnarch position -- you don't have to believe it until you experience it, so you don't have to trust her until you do. leaning towards the dating option--that is seeing if she wants to date and see how it goes from there.
Seems like a fair compromise -- if she's really interested, she ought to be willing to discuss it. But if she's essentially demanding "all-or-nothing," then caution should be your by-word.