First, being a "mommy" of an adult can have its challenges when what you seek is adult behavior in an adult relationship.
The point that he apparently misses and maybe you don't emphasize is that there is more to this than "just talking." To him that probably feels like he is doing something about a problem (yeah, you are talking about it but not actually taking any specific, measurable steps and actions to address the problem you are talking about). He wants to avoid doing something that you want...you want him to show that he can make progress now, now later.
And what is "the prize" for hanging in there a little longer? What will it look like (HE needs to describe this in very specific terms so that you and he knows what the prize looks like and by when this will be achieved). Otherwise, you'll be asked and will have to choose to keep hanging in there for an indefinite period.
In an earlier post you noted some objection to placing some sort of minimum requirement (and concern about seeing it as a "chore"). Well, there are a couple of things about that. Chores can be looked at as something that you don't wish to do and do only because of some sense of obligation to keep things running in some semblance of order. If looking at it as something he (or you) does not want to do, then you probably do not have much hope (together).
However, focusing on what is required to make things work is also appropriate. It creates a prioritization and structure. So, if you get an agreement on prioritization and structure, don't set your minimum to the absolute minimum. Whether you know what it is, we each have an absolute minimum we can and will accept. But there is no sense in setting your expectations at the absolute, bare minimum.
Of course, he could turn you down cold, like my wife did to me. Under those conditions, it sounds like you'd be willing to bolt. Although it is possible to be statisfied with many levels of your life and your accomplishments, you'll have to decide if the legal recognition of marriage are worth it to you to have a non-intimate friendship with a room/housemate.
Not wanting them around is a sign that it might not be worth it to you (any longer) if this is the way it is always going to be.
The Captain Kobayashi Maru
Last sex: 04/06/1997 Last attempt: 11/11/1997 W Issues "No Means No" Declaration: 11/11/1997 W chooses to terminate sex 05/1998 I gained 60, then lost 85 pounds. Start running again (marathons)