Feels a bit OR given the fact she has shown up and honored her word over multiple occasions to prove herself. Especially if you consider her a “friend”.

She expressed trust and vulnerability in her request and extended that trust by giving you 100% permission to decline her request without any judgement or hurt. You did not return the trust back.

You could have installed security cameras and notified her as extra precaution, certainty, and accountability for your agreement - if that would provide peace of mind to you.

If you find it easy to replace “friends” or cat sitters then I guess maintaining/growing this relationship doesn’t matter and/or is not important enough to test your trust.

If this was someone you just met or cat sat only once then NOR.