H is acting like a child who is checking to see if Mom is watching him on the playground. As long as OW is living with him in your home then I would be wary.
A simple thanks will suffice. Wish I could be more hopeful but this is typical "cake eating" behavior and is very common. I would just keep living your life.
Hang in there
M:25 years at BD w/ 2 daughters BD: 5/14 Separated 6/14 - H moved cross country w/OW D Final 9/17
“I can be changed by what happens to me. But I refuse to be reduced by it.” ― Maya Angelou