Based on your profile and http://www.nhlbi.nih.gov/health/educ...MI/bmicalc.htm
Your BMI is 40+ and maybe you should consider doing research on the connection between obesity and testosterone. I'm certain this isn't anything you havent heard from your doc. The combo of increasing age and morbid obesity is simply contrary to a decent sex drive. Talk to your doc about this. It's nothing he/she hasn't heard and you'll get great advice about near and longterm steps.
Also, take the advice above and try an older, larger (non-spinner) provider. In FTW, Lita would be at the top of my list. I'm guessing there will be a few providers that may hesitate consulting with a larger hobbyist. Make sure your P411 (if you have it) profile includes accurate height and weight. The last thing you want to do is show up and be turned away.