As stated before, my case is quite different as the woman concerned and my dh really did not fit and even relatives remarked how ill-suited they were and that there was no spark or love between them.
I have met her and him and immediately mentioned to the friend who introduced us how loveless their marriage was and that I was sure he was cheating.
In very few cases it really is true, that the couple didn't fit and married out of necessecity or to please others, rather than be honest and look for a better match.
So dittany, that does not make my dh a compulsive cheater just because he was married to the wrong person and unhappy in the arrangement. She also shagged away from home and complained how much happier she is now. She has the chance of finding the right one for her rather than living up to someone's standards she can never attain.
What's the point of living to please someone else? Everyone should be entitled to their own happiness.
Anyhoo, back to floops' case, I really don't think she should play nicey nicey and waste her time being nice to the assistant.
I agree with dittany, that it's probably totally meaningless to her dh, but she needs to get it sorted. Playing cool has never helped anyone.
Get your claws out floops and tell the assistant to sort herself out and get off your husband's back. She's spending time with him and getting presents by being disrespectful to you and your family unit.
She'll probably be wide-eyed and nice as pie if you take her aside, but don't be fooled.
Also, I think your husband needs to get his priorities right. Never mind how good his PA is, 230 Pounds is unjustified, esp. if spent on personal girly stuff for her.
Also, sudden changes in sexual behaviour would indicate he's getting new stimulation...it all seems to fit the bill.
Tell her you'd appreciated it, if she would keep her involvement with your dh at a professional level and respect your family and you and his integrity.
As parting words I'd tell her: if she knows what's good for her she'll stop the personal comms and get a life, to stop ruining yours. It would be a shame if her professional career would come to a halt and she'd get a reputation for being a slag.