Worried I found DB too late

[cw68]

I just started trying to stop nagging, stop talking about our R and did well until one little text exchange. Once I realized that I was talking about it again, I sent a message basically saying, "sorry, didn't mean to start the dance again, it doesn't do any good to state the obvious" and he replied that he wasn't irritated by it. I (of course) responded one more time and got the "I know." response.

Other than that, I've tried to do the 180. But how do you do it when you share a house? I've stopped talking about our R, saying ILY, etc. But we still try to spend time together as a family for our kids sake. We're updating our house (new flooring, something we've been talking about for two years and if we do need to sell the house, it's something we need to do) and he still comes for weekend days to do yard work and the like outside of custody times.

Half of me wants to lay down the hard line and show him what it really would be like should we divorce, but in the best interest of my kids I can't just draw a line in the sand.

I guess I understand the no "ILY" things and not talking about our R, but do I need to stop agreeing to dinners as a family and other things? How do I balance the needs of our children and my desire to institute DB/DR to make our relationship last?

And thanks so much for the quick response and support!