Forget about binding. It's something that people do too often for the wrong reasons.
If you have a selectOneMenu like this:
You can set the selection in
Java code by simply invoking the "set" method: "setSelection(newValue)".
Please note that SelectOneMenu has built-in validation, however, and if you attempt to set a value that's not in the selectItems list, you'll have problems.
The secret of how to be miserable is to constantly expect things are going to happen the way that they are "supposed" to happen.
You can have faith, which carries the understanding that you may be disappointed. Then there's being a willfully-blind idiot, which virtually guarantees it.