Re: Wife's male coworker
I completely understand where you're coming from. I had found texts on my wife's phone that were more than inappropriate for anyone other then a husband to send. After looking through her phone, there were no other texts like those, some flirty but nothing I would really call inappropriate. My wife works in a male dominated industry so she needs to put up with a lot, let's face it, as men sometimes we make comments that are less than appropriate in front of women we know well and are comfortable around.
If she knows that you periodically look at her phone, she may be deleting the texts because she doesn't want you to get upset over something that means nothing and she has just come to accept as normal from this individual because that's his personality, it doesn't mean that she's cheating, thinking of cheating or even entertaining any of the texts. Needless to say you do have reason to be on guard, but I wouldn't make a big deal about this as it could just push your wife further away.
Keep in mind, men say things, sometimes stupid inappropriate things, but unless the red flags you're seeing are from your wife's side of things I wouldn't worry too much. I'm not saying to let your guard down or to stop checking her phone from time to time, but don't push the issue with her or confront her on anything unless there is a real red flag from her. If you constantly question her about this it will only push her away and make her withdraw.