Legal Question in Real Estate Law in California

It is possible. If the loan is determined to be community debt then she is responsible to half.

Possibly, but I'd think very unlikely. The "loan" is surely a promissory note secured by a deed of trust, and an action to collect on the note will almost surely be a foreclosure by trustee's sale, rather than an attempt to hold the husband personally liable. Residential lenders almost always look to the collateral, first and solely, and in many circumstances are required to do so by law.

The most likely negative results for your client are (a) impacts from the loss of the property, e.g., if it is their home, she'll have to move when the foreclosure takes place; and (b) since she is married to the debtor, the credit agencies may pick this up and her credit will be impacted negatively.

The obligation might become community debt, but even so, the collection effort would almost certainly be by trustee-sale foreclosure of the property, not involving any allegation in court or otherwise against the wife.

If she didn't sign the promissory note she is not personally liable on the note. But I understand what Mr. Shen states, in that community property can be looked at to satisfy a judgment.