Last and next are notorious words in these contexts. My mother had a stamp convention to go to in Cincinnati. "Next weekend," she says on Monday the 9th. Meaning the weekend of the 22-23, because the 14-15 was "this weekend." Come thursday the 12th, she says, "Remember that convention next weekend? It's this weekend. I'm going to Cincinnati tomorrow."
The lesson is that when you're using this/next/last in these contexts, and you need to be sure, ask for the date!!! :p
I, personally, would say, today, August 15th, 2004, that last July is July of 2003. If I'm referring to July of 2004, I'd say simpy "July" or sometimes "Last month." I would rarely say "this July" (right now) because, for me at least, "this" is usually indicative of future.
(Although, sometimes not.
"I went to California in July."
"This July?"
"Yes, this July. As in last month, a couple weeks ago, can't you tell by my non-existent tan how recent it was, this July." )
My two-cents.
Bethy
