Hello Sir,
It's going very well, thanks for asking :)
Tamsulosin does not reduce the size of the prostate, but rather will allow for dilation of the sphincter that allows for urination (and ejaculation). Thus, stopping taking it will not necessarily induce a risk, but will bring back the symptoms that brought you to see a doctor in the first place (decreased urine stream pressure, difficulty initiating urination).
To decrease the size of the prostate (and possibly reduce the risk of its size becoming problematic), you should instead use a product like Proscar™ (finasteride) or dutasteride (or saw palmetto). That said, taking these medications will also improve your symptoms of decreased urine flow, but it will take longer up to 8-12 weeks. Also, there is no guarantee that taking these types of medications will reduce the long-term risk of the prostate getting bigger because it contains a tumor.
Finally, regarding surgery, it is being done less and less (and almost exclusively when the prostate contains a tumor), because it causes serious and quite debilitating side effects (many men become incontinent..).
Bref, nothing perfect here, but if the side effects of tamsulosin are significant, I would recommend discussing with your doctor the possibility of introducing a drug like finasteride.
Happy evening to you!
Alexander