Hi there,
Don’t be so scared because there are various reasons which are causing hydronephrosis.
Sometimes this condition is caused by a kidney stone which causes obstruction of the ureter. If the flow of the urine is blocked than the kidney most usually get swelled.
When we talk about treatment options it is important to focus on restarting the free flow of the urine from the kidney. This should decrease the swelling and pressure that builds up and by doing that it is decreasing normal kidney function.
Of course the treatment usually depends on the cause of the hydronephrosis. For example if the condition is caused by a kidney stone and your urine flow is not completely shut down the doctor will prescribe you strong pain killers and home treatment until the stone passes.
I had hydronephosis of the right kidney at age 18, my mother at age 40. yes its very painful when it flares up my uncontrollable pain on the right side lasted about 3 days at a time every few months until diagnosed with it and surgery was performed . after my surgery as well as my mothers Who is 70 and very healthy neither of us have had any further problems since then. It is treatable and with todays technology I'm sure has changed a bit. I lead a very healthy life and have had no other problems since and I am now 48 yrs of age. But once you get treated you will feel and be fine. Best wishes and hope my post puts you at ease.