Well I'll be honest with you, if you say all that, you're probably going to really provoke her. It sounds more like you are taking a stand than just trying to protect yourself and her feelings at the same time. Not that I think there's anything wrong with that. But I think you might want to consider what you are really wanting out of the conversation. If you really do want to spare her as much as possible, all you need is

"I've realized I need space outside of work and need to ask you not to contact me outside of work anymore. I enjoy working with you but need that space."

Then if she seems even slightly receptive to the idea, follow up with

"Thanks for being respectful of my feelings, I really appreciate it."