Hi TA - I struggle, too, with doing too much for my H vs. being cold/punishing/vindictive and the ideal spot between those two extremes. I over-think a lot as well and often wonder if me doing or not doing something is being "too nice," or just being polite, since it sounds like we should still be polite! My "measuring stick" questions, so to speak, that help me with these decisions are "is what I'm doing something I would do anyway? if H fell off the face of the earth would I still do it?" With the example you gave above about dinner, if you're cooking dinner that you want, when you want, and there's extra, by all means he can have it! But I don't go out of my way to ask him what he'd like, or wait until he gets home to see if he'll want it, etc. It's always something I'm doing anyway, and if he happens to want in on whatever it is, fine, but I'm still doing it! You wouldn't be making him lunches if he fell off the face of the earth : ) I'm trying to think of my H like a random college roommate - I should be polite and cooperative so that we can live together comfortably, but don't really consider him when I make plans for myself.
Hang in there! I'm right there with you on how tough it is to live with your H and have no idea if they're in, out, or still thinking about it.
Me:30 H:29, no kids T:12, M:4 (when D was final) 12/13: "Don't think I want to be M anymore" 6/14: Separated (I move) 1/15: H filed for D 5/15: D final