Nine years with a man who thinks this is faintly comic

My partner of nine years finds all of this faintly comic and completely fine. He is not tolerating anything. He genuinely does not mind, in the good way, and asks how my evening was in exactly the voice he uses to ask about my sister.

Thirty five, the city centre, five years in. What I am looking for is a second relationship, and I want to be precise about that word, because people hear the shape of my situation and imagine something much looser than what I am describing. I want one rope partner, over years, with a standing evening, who I care about and who cares about me.

The practical questions are most of it and I have answers to all of them. He knows where I am. Nothing is hidden in either direction. He does not want to meet anybody at first and probably will eventually, because in my experience the version that fails is the one where the person at home never becomes real to anyone.

What I need is somebody for whom a second position in my life is genuinely sufficient. Not a stepping stone and not a slow campaign. Two people have told me they were fine with it and meant it for about seven months each, which was long enough to be properly disappointing.

Not looking for a man who needs telling that he is the more important one. Not looking for someone with no other life of their own, because I cannot fill one and it would be unkind to try.