Clearly, I am not Leigh
, but speaking from personal experience it gets harder for me to lose weight as I approach my goal. Just for me, it requires me to be even stricter (and it sounds like you're doing that) as well as changing my workouts. Even something as simple as adding on a mile walk with the dog a few days a week can be enough to get me losing again.
I'm sure you will get great advice here as to whether a break is in order.
You've done a great job on those first 18 lbs! Congratulations!