I was noticing this in a couple relationships also. One person took my telling them that "I can't do this right now" AOK.
The other person was incredibly put-off. And continued to needle at it. To be fair, I was initially pretty darn wishy-washy stating that it wasn't working. When I finally stood up, she was hurt and angry; I was upset that I'd hurt her and that she didn't understand and I didn't want her to think I was just being a b-tch -- I wanted to EXPLAIN and make her feel better.
Then it hit me: I was still trying to make her happy - still people pleasing - still worried about what she thought of me.
And then CatsPajama's tagline came to mind: What other's think of me is really none of my business.
The first line in the quote that FindingPeace shared is amazing. How did I miss that one last week???