Here's an idea in the meantime:
Is she crate trained? If so, get one that is oversized for her tiny self. Put a bed in there and take one of your old oversized T-shirts or sweaters and lay it on the bed in the crate w/ the door open. I'd put this crate in an area where your house typically gets the most traffic or near your bed.
The idea is that she can still "be" w/ you, while your away. She probably snoozes a lot when you're not there (on those days that you didn't bring her w/ you in the past) anyway, and this way she'll have her own little secluded place that she can retreat to and wait for mom to get home.
I've had many clients do this to help transition a dog and it's a trick that usually does the key! Further if/when you get this big dog, she'll have her own area to get out from underway, especially if you get a large breed puppy.
m2c