How does one get an insane wife committed?

Have her doctor that is treating her to commit her.

Ask her doctor about having her committed. You can also call a mental hospital and explain it to them and they can commit her.

Ask her doctor about having her committed. You can also call a mental hospital and explain it to them and they can commit her.
The hospital cannot commit her and will not, especially if they have never seen her before. An M.D. who has been treating her is the way to go.