thoughts on top of the line Trek FX or other lightweight bike

[brigada]

I see. Pardon my assumption, then! Unfortunately, stock bikes will be kind of heavy in that price bracket nowadays, no matter what you buy. You might have better luck buying used if weight is the priority, but you'd still need to get it serviced and perhaps replace some used up parts... I don't know if that's an option?

[Scrappy]

Have you thought about some of the higher end folding bikes? For approx 2k you can get a very lightweight folding bike that will ride like a "normal" bike and be much easier to carry. A high-end Dahon would fit that profile nicely