G, I think your email was very detached -- which may have been why his response was so detached too. Like Lisa, I've found that my H tends to match my mood (although that is starting to change a little bit). It is scary to be the one to thaw the ice sometimes (due to fear of rejection on my part, I think), but if I do it without expectations then I find that I can handle whatever response I get.
I actually admire your restraint. I really don't know that I'd be able to resist a temp check at this point, however damaging that may be.
I second Lisa's suggestion that you invite him to drinks. It's been what, a month, since the last time? Just be prepared for him to say no thanks.