Friends-to-be or Real Friends

Had a dicussion about "friends", here is what I said,

"Personally, I won't say anyone in the world "is" my friend. I will say anyone "could be" my friend. I had some chats with facility guys while I was doing orientation for my school; I smiled to people on my way back home; I said hello to someone I met at the door of grocery store. I wasn't doing that because I think they were my friends and I would feel insincere if I said so. I didn't actually know them. But I was showing my respect to them as good human beings. They could be my friends if we had time or had chance. But we didn't. So I can only say they were acquaintance, or "friends-to-be" for me.
I used "real friends" here because I felt like that is the kind of friendship being talked in the article. There are always some people I would think of frequently even though we don't have chance to meet with. Everytime I think of them, I would wish them happy and have a good life. And if I feel lonely, they are people I want to pick up the phone and talk to. These are my real friends, and they currently are."

In English there is a word "friendly", we are told to "be friendly" to other people. It doesn't seem to make sense to say "to be friendly to your friends", right?