From what you’ve described, it sounds like she’s a straight forward and direct person, which is good. Just be straight forward and direct (but tactful) with her. Something like, “I’m sorry, I think I misunderstood the situation. I’d like to hang out as friends, but I’m not looking for anything more.” Optionally, “We can have that drink if it’s just as friends, but I’m not going to lead you on if you want something more.”

I got the Logitech Lift and found it didn’t do it for me. It’s certainly better than a traditional mouse, but it’s at an angle that’s still not neutral. I ended up getting an Evoluent and it was much more comfortable.