A few years ago I bought her Eagle Optics Triumph 8x25, but she wants something better. She values light, compact binoculars. I found a used Stokes Birding Series Talon 8x42 on eBay, but she thinks they are too big and heavy.
If I could keep it under $200 I would appreciate it, but I may need to push it to $250.
Nikon Monarch M5 8x42 would be a good choice. They are 20% lighter than the Stokes model. You’d have to go to a smaller objective if she really hates the weight, but most birders prefer 8x42 as the optimum compromise between weight and brightness.
Check out the reviews, especially on birding sites - everyone rates them highly. And they are sold everywhere, so if you are not in an immediate rush you will certainly find a discount somewhere that brings them into your price range, list price is $290. And a healthy second hand market, either to buy or to resell later.
Does she wear glasses? If so, eye relief is an important factor. I have a pair with 15mm and one with 17mm of relief and the latter are a huge improvement.
Just to note that there are several iterations of these over these where Nikon has changed the name slightly. I think the last prior version was called just “Monarch 5”. Some of the second hand binos on Ebay will be the older versions. I honestly don’t know how much performance difference there is between the versions, but there’s certainly a significant $ difference.