To echo what's already been said....
I'd track those calories REALLY closely for two weeks. I mean REALLY closely - measurements, weights and each and every bite, lick, taste, crumb and sip that goes down your throat. You want to be absolutely certain that your calorie counts are spot on.
Also take a look back and think if you've had any "off" days or meals - because that could really stall out your weight loss.
Not sure if this IS a factor, but how is the "quality" of your calories? I know for me grains, yes even whole ones, don't do well with me. I am very carb sensitive. I eat plenty of them, but those found in veggies and fruit.
How is your water intake?
And again, if you're not doing any strength training, I'd DEFINITELY add that in - like NOW. If you've been steadily doing 45 minutes on the treadmill, perhaps you'd like to INCREASE it to 60 minutes. Or switch it around, one day treadmill, one day some other sort of physical activity - an aerobics class, zumba, swimming, bike riding, something different.
Giving up is not an option, ya hear? You have done incredibly well, but yes there's more you've got left to do, so none of this silly talk.
Hang tough. A closer look at your food menu, a little more activity, a tweak here and there, a bit of patience and before you know it that scale will be headed down once again.