Relationships between people are between real people, not merely ideas. We have ideas about our relating and ideas about other people, but the relating and people are actually real and not reducible to our ideas about them. While I’ve found that improving relationships with various parts of myself has improved my relationships with other people, it does not follow from doing so that I don’t really relate with other people or that other people are really just projections of my consciousness.
To give an example, in second grade I had a crush on a girl for the first time. Since I never approached this girl and shared with her about my feelings, my idea of our relationship became very distorted compared to the actual relating we did. Our actual relating consisted of being in some of the same classes, but did not go much beyond that. My fantasy of our relationship on the other hand involved a mutual romantic interest. If my relationships were only inside of me, I couldn’t even make this comparison between the idea of our relating and our actual relating.