I think you are doing a great job, keep up the good work.
Did you ask your aunt and parents about more training sessions?

I was thinking about what you said about Alex not really being food motivated, don't feed her before your training session that way she will be good and hungry and will pay more attention to your treats. When you are all finished training then go ahead and give her, her dinner. Be sure she sits until you(or whoever) places the food dish on the floor. To practice this say sit, and start to lower the bowl, if she gets up say "oops" and pull the bowl back up, try again start to put the food down, if she gets up say oops and pull the bowl back up ( standup). It won't take long for her to figure out the program. You gradually work up to having her wait after you set the food down before she eats it.

Also you might want to keep a journal of her progress so you can see how far you two have come and so you know where to start on your next training session.
Good luck, can't wait to hear how the next session goes.
Gina