Is her thinking I "gave her a bad deal" better than hurting her?

Maybe it's just me, but I don't mince words on these things---and my friends know it. Tell your friend the truth. If she is making comments about it somehow being your fault, you can let her know the deal and move on.

You WNBTA for that. You don't have to be mean about it and frankly, it's easier when you don't hide it for a long time. If she wants to make that an issue, then she would TA.

Also, stop worrying so much about "hurting her." Is she not a grown ass woman? If she can't handle feedback about raising a cat, I suggest you get some more mature friends.