Well, legally, when you supply someone as a reference, they can only say that Yes, you worked there, and what dates. Anything else has been determined to be heresay (hearsay?). But I would still try to find some other way to fill in the time you worked there.
I ain't real happy with my boss, either. Not to the point where I want to risk my job, yet, but I have done the exact same thing you have. I had a boss that told me "Well, if you're so unhappy here, you can leave". My response, "Give me five minutes to clear out my desk, and I'll give you my key." He was kinda suprised when I handed him my key, too.
And, when I was at UPS, my 19 year old supervisor (No offense to our kids here) took it upon himself to start tossing stuff out of the truck I was loading. So I told him "You're having so much fun, it'* your truck now" and left. His
boss called the next night and left a message "Well, I guess you're not coming in, huh?". Well, duh!