Well I can relate to this, that's for sure. X-rays will typically not show rotator cuff injuries, you need an MRI for that. Have you had any traumatic injuries to your shoulders? If not, I'd try this before I even considered surgery.
Take 2 grams Glucosamine per day (1g in morning, 1g before bed)
Drink at least 1 gallon of water every day
Do [url=http://familydoctor.org/handouts/265.html]Rotator Cuff Exercises[/url] 4 times a week. I'd also add upright barbell rows and front and side delt raises to this routine. Make sure to ice your shoulders for at least 15-20 min after you do these exercises. A frozen bag of peas works well for this.
If you lift weights, avoid military press and ALL behind the head exercises.
The glucosamine takes about 2-3 weeks to start working and you won't see much benifit from the exercises before then either. Do the above for one month and see how you feel. It's helped me a lot.