For peace of mind I really suggest a polygraph. I would also tell your wife she shouldn't delete any text message anymore until you have seen them. A trust has been breached and I think it is appropriateShe did tell me his son recently died and her explanation for some of the days texting him while she was at work was to get info on food/drink as her work held a condolence type party (not the best word).
The job thing throws me off and I won't know unless I talk to the manager/owner. She's worked there for four months and hit a raise each month for the first three months and got the promo on the 4th month. She left her original career (which was much faster paced) and was doing this job while studying to go into a different field. When she quit, they gave her options to go back to the original position before the promo or to just work part-time. They also told her to basically come back whenever she wants and they will hire her back. She's been at the same level of stress at other jobs and has not quit so abruptly. And she didn't give a two week notice. Called me, said I want to quit and then quit.