Re Lostgal M: Wha? I'm not picking on you. I'm not thinking of you here. The damn dog can't walk. I'm
A better way to state this would be:

My intent was, what would make the dog's walk easier given his arthritis condition. You have no fault in this.

Leave out M: What's that look all about? and The damn dog can't walk.

In reality, the dog can walk but has lots of trouble walking.

When you said "that look" it was/became about him to your H, not the dog.

H: Its going to lead to an argument.
If this happened to me and BB, I would have thought something similar LG.

I hope some of the differentiation post help you. I think they are helpful in situations like this.

Lou