I ride a bike too. I ride on average 200 miles a week on mine. I also end up being on the road at night a lot of the time especially at this time of year.
I have a Camelbak and I love it. I would highly recommend you get her one, they are perfect for bikers. What ever model you get for her, make sure you get it in the Hi-visibility color scheme. I have a Hydrobak 07 model in the hi-viz color scheme. It reflects headlights from cars very well.
On the Camelbak website (HERE) go to Sports/recreation, then hydropacks, view all, then it is the last one to the right on the top row.
Just out of curiosity, why have you not gotten a bike and joined her? It is some of the best exercise you can get and it is a hell of a lot of fun. Something you and your spouse can do together is always a good thing.