Disclaimer: Everyone's situation is different. While some are similar, what happened in one isn't guaranteed to happen in another. However, hearing other similar experiences can help us learn. That being said ...
I distinctly remember Memorial Day weekend 2007. W out of blue was nicer than she'd been to me in months and suggested me, her, and the boys go away for a fun weekend like we used to. Ended up at her family's for part of the weekend, mine for the rest, in general having a good time and feeling more like a family than we had in a long time.
Turned out she filed for divorce the Friday before and I was "served" on Tuesday.
I urge caution on reading too much into friendly interactions and trying to figure out their motivations.
Everybody hurts. It's part of life. Don't miss the good stuff.