Somebody had to be taking that video for her to send to him and I bet it was her next fuck. Probably one of his friends. But there is nothing wrong with that.
You're right---I'll be willing to bet she's getting more cock now than when her husband was home. I know that was the case with me and my wife. I stayed gone a lot--and she fucked a lot. But I did too and I got my share of wives too.