Originally Posted by bassist1962
You wll hear this mantra - 'Get a Teacher!',
Or not, since she already HAS a teacher.
But this does seem a little slow; are you taking lessons weekly and how much time do you spend practicing daily? Progress is a direct result of focused time spent practicing and playing, so if you are only doing that an hour a day, you can't expect to make the same progress as someone who spends 4 or more hours a day.
If, by chance, the lessons you to which you are referring are GROUP lessons, you may want to take heed to bassist1962's advice and find a private instructor.
Getting to thumb position without having a good solid foundation in the lower positions isn't any easier than building the foundation first and THEN getting there. No quick and easy, it's the "P" word.
Have you asked your teacher and what did they say?