I don't know about that. She said straight up, if the weight is an issue, leave her. I would have said Until/unless you're at peace with who she is now or you start communicating better DO NOT HAVE ANOTHER CHILD WITH HER.
I would have suggested framing it something like this. I am worried about our dynamic and how it will impact our future. I am concerned about your weight and health, and I can’t seem to be supportive or helpful. It’s simply not in my nature to be quiet, so I don’t know what to do. See what she says. If they’re not having sex, and the weight/resentment is factoring into it, then I’d mention that as gently as possible. But maybe not in the first discussion. You might need to let this new tact percolate for a while.