Hi G,
Great question, I'm sure others have more views to share.
The two profiles should obviously be merged... to prevent any feelings about that from being directed at you, you could instead enter into the process as an equal participant and the two of you together are following procedure by combining the two.
Once they are merged you could send a big fat thank you very much etc.
Then I would remove her or anyone else besides myself who was a manager of my profile. It's up to you if you want to leave her on the trusted list or if you feel she could see plenty without. Your feelings might depend on how close you are to her or how much you literally trust her.
To prevent ill feeling when she notices, you could pre-emptively inform her of what you are doing and suggest (because you care about her) she do the same.
I hope this is of some use to you. Enjoy the day!