Dominant activities

It is the law of cause and effect.

Depression causes one to be submitive.

So if one person who is depressed start to have dominant activities then he can reverse his depression.

He has to want it and to make efforts. He has to find things that make him stronger.
As an example he can go to gym everyday and he will try to make a strong body. If he find something that likes a lot, a meaning to his life then he will stop to be depressed at zero time with no efforts.

Your wife can find a meaning in her life like she is useful to u. You need her in your life.

If the cause of Depression is something physical things are tougher.