I don't think you were wrong for initially keeping them as friends, just like she also wasn't in the wrong for being uncomfortable with it. It's a matter of personal boundaries, and that's where honesty and communication come in which is what you lacked. I also hope you know that there's plenty of wonderful people in the world that won't be put off by stuff like that, even though your choice of not putting Sabrina or any future partners in that position is also perfectly valid.