If her swim bladder is damaged then there is not much you can do. She may survive a long time this way. I had a goldie with swim bladder disease and she lived for 4 months that way. She still ate her meals every day so I saw no reason to end her life. I let her pass on her own. If she is constipated it may cause her to swim this way. You can pinch some green peas out of their skin like pinching a grape and see if she will eat 5 or 6 of them. The fiber will help her to loosen her bowels. If she still swims sideways after a day or two then you know she has the swim bladder problem. It will be up to you to decide if you want to let her live this way. But PLEASE do not ever flush a LIVE fish down the toilet. Chlorine in your water will strip her slime coat off her body before she dies. This is like dipping your skin in acid. It burns and would be a horrible way to die. There are more humane ways of euthenising your fish. Check www.wetwebmedia
My Goldfish Is Mostly Just Floating On His Side And When It Tries To Swim, It Is Upside Down And Out Of Control. Is There Anything That Can Be Done For It?
Well besides giving her a swim in the tolet nothing really either she ate too much or she got her air sack popped and it can live like that bad it's hard so just wait it out and see what happens