Cost of Tobramycin for Bronchiectasis and the Medicare "GAP."

Hi everyone, Haven't been here much and will spend more time. Been over in the lupus group. Do any of you have lung problems from Sjorgren's? Sjogren's aka SICCA has caused bronchiectasis (adult version of CF) in my lungs. My lungs are dry and my breathing tubes from large down to nano are all dilated. I use a nebulize to remove secretions from my lungs 2x each day. Plus 2x/day the tobramycin for preventing pseudomonas reinfection. The medicine is very expensive--Tobi (tobramycin) for inhalation. It can cost up to $7200.00 for a 28 day supply. My pulmonologist wants me to be on 28 day cycles every other month forever to treat pseudomonas. The cystic fibrosis kids get lots of help, rightfully because they're kids. Been surfing the web and not finding much support for us oldsters who live on the financial cusp. I'm 66 and on Medicare with an HMO. I just fell into the drug "GAP" in the Medicare drug plan coverage. Which has a higher copay up to 100%. The dose I'm using now was paid by the plan before the GAP. I have to pay for it 100% because the plan doesn't cover it in the "GAP. " See the price above. I don't know anyone who could afford this every other month. Has anyone been prescribed this drug? How were you able to handle it? Do you know some resources? You got to hold on.