I'm wondering what is the actual subject in this sentence: "One of the countries she has visited that I have not is Canada."
To me, everything up until 'is' seems like the subject, but I can't find any information about relative clauses being found in a subject, other than in the case of a 'that' clause that comes first (e.g. That she should forget me so quickly was rather a shock).
If anyone could parse this sentence for me, I would greatly appreciate it! Thanks for your time.