There wasn't really any reason for Natasha to not just spill it all out to Jessica. Honestly, there was definitely a point in time where she would have. Back when she was still Oktober or Natalia or any other number of aliases that she'd burned away when S.H.I.E.L.D. burned down. The ones that had so expertly and neatly drawn all those red lines in her ledger. One by one. Mission by mission. Kill shot by kill shot. That woman wouldn't have been stood here hesitating, leaning into her (impressively top shelf) liquor and trying to find the right words for what she'd seen that... well, what she'd been shown? How did she even describe it, she hadn't lived it after all. She could play the part of having lived it to an extent, it had felt... weird after the first time she'd gone down to the amber. Weird to be in her skin. Weird for her hair to be getting long and red again - so she'd chopped it back off, bleached it to the blonde that matched her memories. The woman who would have watched Jessica squirm (because anyone would squirm, even if it wasn't externally - anyone would squirm at what she was about to have to tell the darker haired woman) didn't exist any more... but she wasn't even sure the Avenger existed any more.
Berlin had happened. She'd let... James and Steve go. She'd gone off on their little nomadic savior adventure with Wanda and Sam. She'd avoided even a phone call to Clint. She hadn't reached out to Bobbi, even though knowing the other woman had been black listed too had made it very temping. She almost didn't recognize the woman in the mirror, she definitely wasn't Natalia any more. But sometimes she was even wondering if she was still Natasha or someone else entirely. She had always been good at that... reinventing herself. Too good at it really. It was probably just the shock and removal from her friends that she was feeling right now. Honestly, with everything she'd been through in her life it probably wasn't shocking that she might be having a little bit of an identity crisis at the moment.
At least, when it came to Natasha, it never held her down - just tickled in the back of her mind in the early hours of morning when she was staring in the mirror. And... right now... as she was staring down the barrel of words that could be taken back just about as easy as a bullet could.
"Ya, good guys. Far as I could tell. I mean, I trust Thor's judgement and all that but uh..." She down the rest of her glass, holding it out towards Jessica with a sarcastic little shake - the most she could manage right now to shake the sinking feeling. She was a strong woman. She was probably one of the most emotionally competent and resilient people out there. But there was a hell of a lot to what she was about to say and she was pretty sure it was reasonable for even her to have some cracks in the surface right now. "Thanos got all of them, Jessica." She said, looking the other woman straight in the face. "All of the stones. I uh..." She reached up with her free hand and push her hair back, "I don't know if Rocket is from when I'm from. I think he can't be from too much earlier. He knows too much about Earth and humans. But... listen, if I tell you how it all ended. How the fight ended, its... a lot. I'm not putting that on you with you knowing that its a lot. Maybe too much."