@CatharineMeyers 

Happy to provide a few more suggestions!  Hybrid bikes are a great way to get the best out of both worlds. Something you might consider as well is a stem raiser. This can help you elevate the handlebars changing the geometry up a bit and hopefully putting less pressure on your back. The higher you can get the handlebar the less aggressive riding position you’ll be in. 
Here are a few hybrid considerations:

Cannondale Althea 1 

Cannondale Quick CX 3 

CO-OP Cycles CTY 1.1 

 

Here is a link to a stem raiser as I mentioned too:

Delta Alloy Stem Raiser 

If you decide to go with a raiser it may involve a few other bike alterations but could ultimately get you on a bike you really like!

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