Why won't my doctor have me get surgery, my shoulder is very very weak instable i want to play water polo but can't bc of shoulder problems?

Muscle Weakness: One does not just get surgery. If your muscles are weak and unstable then they must be strengthened. This is usually done with physical therapy, not with surgery.

Strengthening Exerci: The best treatment for shoulder instability is strengthening exercises. Shoulder ligaments cannot be strengthened. I suggest you visit the following website to get a shoulder strengthening regimen. Most surgeons will only consider surgery after conservative approaches have failed. http://www.nhs.uk/conditions/dislocated-shoulder/documents/100419shoulder%5b1%5d.pdf.