Hi there Rhonda,
I can relate to poor timing on important issues. I've learned the hard way that timing is important, but also figuring out what works for your spouse is also important. What I have learned in my relationship is to not be combative about an issue my husband is upset about, and to just let him vent. It's gotten easier as I remind myself it isn't personal, even though it feels very personal! When my husband has had some time to simmer and relax, I can actually make a joke out if it. He's usually mortified and sorry for being a jerk, and even asks if he is usually a jerk (which he's not).
The other thing that may be helpful is if you know something about the type of work he does, to ask questions that show that not only you care but that you've educated yourself to better understand him.
I've found that open ended questions are the best, as well as never to say "We need to talk" or "We never spend time together". That seems to set off guys alarms!
Hope that is helpful,
D.