Osteopenia Caused by Corticosteroids?

40 year old pre-menopausal, white female. No family history of osteoporosis,  large build (5 ft. 9 inches, 185 lbs), and have healthy diet. Exercise regularly and take the appropriate supplements (multivitamin, calcium/vitamin D.) Have taken inhaled corticosteroids for 15+ years for mild asthma.

Had a recent DEXA scan which showed average lumbar bone loss of -.9, which puts me in the osteopenia range. The numbers ranged from -.2 to -2.0. My doctor (endocrinologist) did not even call me with the results. I am upset about this and unsure about what I need to do:

1. Take 4 puffs daily of Aerobid, and 1 puff per day of Proventil. Do you think the Aerobid is the main culprit in premature bone thinning?

2. Are there any other tests available to test calcium absorption, or is this point even a factor?  

3. Do you have a recommendation for your patients with this issue in regards to Calcium Carbonate supplements versus Calcium Citrate?

4. Should I refrain from any type of heavy lifting activity for fear of compression fractures?

5. I took Singulair in the past for a few months, but had to quit due to chronic ear pain, which persists. With that in mind, are there any other medications available that might lessen my need for inhaled corticosteroids in maintaining my asthma? I hate to "rock the boat" by changing meds that are working, but if these same meds are putting me at risk for osteoporosis, then I need to weigh all of my options...

Thanks!