Install 32-bit java. Uninstalling old versions is left as a choice for you. Personally I do it. However I don't re-enable the security alerts because then I'd have to go through the process of tediously adding them all back again.
Close all browsers.
Dunk head in bucket of water.
Install 64-bit java
Live on in a world with both 32- and 64-bit java, knowing that at the very least your head should be dry again within an hour.